Dashboard Clock goes off?

[skoya]

Hi,
When I started the car this morning,the clock and BC indicator suddenly goes off.Anyone has idea what it could be??

[jRoss]

Try the knob to the left off the steering wheel, turn it til it clicks

[skoya]

What knob?There is only for the mirrors and headlights

[jRoss]

It's the like a spinny switch that adjusts the dimness of the gauge cluster, i believe it's right under the cup holder. I accidentally hit it one time and the clock light would go off when i turned on the headlights, i thought something was wrong. It took me taking it to autozone and a little experimenting.

[CTScott]

Most of the European ones do not have a dimmer rheostat like our US ones do.

What year is the Yaris?

And, does it have the digital or analog instrument cluster?

[skoya]

The Year is 2006,and the cluster is digital.

[CTScott]

The Year is 2006,and the cluster is digital.

OK - So definitely no dimmer rheostat.

Check the 7.5A MET, 7.5A PANEL1, and 7.5A PANEL2 fuses all of which are in the fuse panel that is under the bottom of the dashboard.

[skoya]

That is left under from the steering wheel,when I remove the panel,right?

[CTScott]

That is left under from the steering wheel,when I remove the panel,right?

Yes - If your car is left hand drive it is to the left of the steering wheel and and it is under the bottom of the dash, so you look up from the floor to see the cover, which has the labels.

[skoya]

Ok Scott,
I have checked the fuses,they are Ok.I disassembled the cluster,and there where no bulbs.What now?

[CTScott]

Ok Scott,
I have checked the fuses,they are Ok.I disassembled the cluster,and there where no bulbs.What now?

What parts of the instrument cluster are still working properly?

[skoya]

Everything works as it should be,only this right corner,where the clock,trip computer and the MPG shows,that part is out of light.When I took apart the cluster,I notice that this particulary part containes small LCD display which is attached to this connector.And behind that is small circuit board that controls it.I did not see any bulbs.Maybe it is an electrical failure,or something like that.

[CTScott]

Everything works as it should be,only this right corner,where the clock,trip computer and the MPG shows,that part is out of light.When I took apart the cluster,I notice that this particulary part containes small LCD display which is attached to this connector.And behind that is small circuit board that controls it.I did not see any bulbs.Maybe it is an electrical failure,or something like that.

OK. It does sound like a failure of a portion of the cluster's circuitry. If you have the owners manual for you car, take a look to make sure that it is not simply a case where you can some how turn off those items.

[skoya]

I have both owner's and repair manual,and I can't see nowhere that problem.
Altought I've downloaded the owner's manual,and it's only for US and Canada models.European couldn't find nowhere.I need it exactly for digital cluster,anything else is useless.

[CTScott]

I have both owner's and repair manual,and I can't see nowhere that problem.
Altought I've downloaded the owner's manual,and it's only for US and Canada models.European couldn't find nowhere.I need it exactly for digital cluster,anything else is useless.

I have parts of the European service manual, but it does not indicate being able to turn off the clock. Sometimes the owners manual has some additional information on those kinds of "features".

[skoya]

I have parts of the European service manual, but it does not indicate being able to turn off the clock. Sometimes the owners manual has some additional information on those kinds of "features".

I don't know man,what can I do?Do you have something else on your mind?
Any answer is a welcome.

[CTScott]

I don't know man,what can I do?Do you have something else on your mind?
Any answer is a welcome.

Other than one of the connectors having been loose, I can't think of anything else that you can easily check. At this point, if you can find someone with another Yaris with a digital cluster, you could try swapping the two to verify that the problem is with the actual cluster.

[skoya]

Other than one of the connectors having been loose, I can't think of anything else that you can easily check. At this point, if you can find someone with another Yaris with a digital cluster, you could try swapping the two to verify that the problem is with the actual cluster.

I will try with this connector,but not today.I will have to wait til weekend.
We don't have much Yaris in my town,so the second option falls thru.
By the way,I forgot to tell you,there is a smaller connector that connects speedo gauge with the hausing,or something like that.Anyway I will try to do something.Thank's again.

[CTScott]

I will try with this connector,but not today.I will have to wait til weekend.
We don't have much Yaris in my town,so the second option falls thru.
By the way,I forgot to tell you,there is a smaller connector that connects speedo gauge with the hausing,or something like that.Anyway I will try to do something.Thank's again.

I happen to have a European digital cluster that I imported to experiment with. When I have a chance I will open it up and see if there is anything that I can think of that would cause the behavior you are seeing.

[skoya]

I happen to have a European digital cluster that I imported to experiment with. When I have a chance I will open it up and see if there is anything that I can think of that would cause the behavior you are seeing.

Great,you do that,thanks.Then send me a PM.

[skoya]

Here is the cluster and the clock on the right side

[CTScott]

That is the one that I have. I just disassembled mine and hooked it up on my test bench to experiment with it. The clock and odometer are a separate assembly from the rest of the instrument cluster. Does anything at all display on the clock area of yours?

50263

[skoya]

No nothing.Did you find something that can be replaced,or behind that LCD is a small electronic board.Maybe there is a malfunction,somethin broken or burned?

[CTScott]

No nothing.Did you find something that can be replaced,or behind that LCD is a small electronic board.Maybe there is a malfunction,somethin broken or burned?

The small LCD (which is actually a vacuum fluorescent display) for the clock and odometer is a separate assembly, so that could be replaced as it may be the bad part. There are three separate circuit boards - The large main on, the one that the speedometer display is mounted to, and the "Core" board, which snaps to the back of the large board. The Core board contains the primary processor for the cluster and it has the EEPROM where the odometer data is stored. Unfortunately you can't buy the boards separately from Toyota, but if you can track down one from a wrecked Yaris, which has a cluster with the same part number, then you can either swap the clock/odometer display onto yours or you can swap your core onto it.

[skoya]

Yeah,but used clusters cost over 100$ on ebay,so it is a bit expensive.My dad is a electrician,so i wil disassemble the cluster and give him.Maybe he can find the problem.Anyway thank you for your response,i will notify you if i find something.

[CTScott]

Yeah,but used clusters cost over 100$ on ebay,so it is a bit expensive.My dad is a electrician,so i wil disassemble the cluster and give him.Maybe he can find the problem.Anyway thank you for your response,i will notify you if i find something.

It looks like there is one driver for both the small VFD and the large one, so my bet is that it is the VFD itself. I have a couple of right hand drive Japanese digital clusters that I pulled apart a while back. I noticed that the small VFD is identical between the JDM RHD one and the European LHD one. I swapped one of the JDM ones into the European cluster and it works fine. I have a couple of them, so if you want to try one let me know.

50267

50266

[skoya]

Ok,i am interested,tell me how we gonna do this.But i still need to be sure where is the problem with my clock.Give me few more days to test it,then i am going to let you know.

[skoya]

Ok,i am interested,tell me how we gonna do this.But i still need to be sure where is the problem with my clock.Give me few more days to test it,then i am going to let you know.

Here is the Pic of LCD.I was wondering this black spot in the right corner,is this ok.I mean I see on both of yours it is visible.Then again as i disassembled the speedo,it had also two of these marks,so i think this is ok.

[CTScott]

That black spot does appear to be a normal part of how they manufacture the VFDs.

Since it is custom I can't find a data sheet for it. It would have been good if I could so that we could take some comparative measurements to determine if that is what is bad on yours.

[skoya]

That black spot does appear to be a normal part of how they manufacture the VFDs.

Since it is custom I can't find a data sheet for it. It would have been good if I could so that we could take some comparative measurements to determine if that is what is bad on yours.

When I loooked at it,from each angle and side,i could not see any soldering error or something like that.It leaves now to test this small circuit board behind it.Then we shall see.

[CTScott]

When I loooked at it,from each angle and side,i could not see any soldering error or something like that.It leaves now to test this small circuit board behind it.Then we shall see.

The driver circuitry is actually on the bottom of the large board (where the large can shaped devices are). The small board on the back is the core board where the odometer data is stored and the main processor is located. I believe that that one is fine.

[skoya]

Ok Scott,here on this pic you can see these three transistors or whatever they are,seems to be burned.You can tell by their middle pins.I have isnpected them with ohmmeter,and the current flows on both sides instead of one.They are type MK 58.So when I turned the cluster on the other side,you can see clearly brown spots on this green pattern.Can you confirm that this could be the problem.You can see them right in the bottom middle section.

[CTScott]

Ok Scott,here on this pic you can see these three transistors or whatever they are,seems to be burned.You can tell by their middle pins.I have isnpected them with ohmmeter,and the current flows on both sides instead of one.They are type MK 58.So when I turned the cluster on the other side,you can see clearly brown spots on this green pattern.Can you confirm that this could be the problem.You can see them right in the bottom middle section.

That could be the problem or at least part of it. On mine all six of the transistors in that area check out correctly with the ohmmeter. I believe the 58 is a date code, since mine are all MK 61 on one cluster and MK 68 on another.

[skoya]

That could be the problem or at least part of it. On mine all six of the transistors in that area check out correctly with the ohmmeter. I believe the 58 is a date code, since mine are all MK 61 on one cluster and MK 68 on another.

Where can i buy these.Is there anything on ebay,or some another web page.
And i need some characteristics for this type.

[CTScott]

Where can i buy these.Is there anything on ebay,or some another web page.
And i need some characteristics for this type.

I am not sure. The MK alone is not enough information.

[skoya]

Hey Scott,can you please help me with this transistor.I could not find nothing with this code MK 58.It has to be another name for it.

[CTScott]

Hey Scott,can you please help me with this transistor.I could not find nothing with this code MK 58.It has to be another name for it.

The number is just the date code. Unfortunately the MK portion has not been enough for me to figure out exactly what it is either. The only thing I can think of at this point would be for me to remove them off of one of mine.

[skoya]

I would be very grateful if you can do this for me,that's if you don't need them anymore.I need three pieces.

[CTScott]

I would be very grateful if you can do this for me,that's if you don't need them anymore.I need three pieces.

I have one of the right hand drive ones that I just use for harvesting parts, so I can definitely ship you the three. They are tiny enough to be able to ship in an envelope as a first class letter, so shipping would only be $2.

[skoya]

Ok tell me what you need from me.

[bs00944]

@CTScott

I have also problem with the digital display clock... Suddenly the clock started to fade...and in half an hour it was complete black.
I think it is burnt.
Do you have any of these modules available?
I have a Yaris 2007 3d VVTi 1300.
Thanks in advance!

[grgo]

I have also problem with small display...
@skoya - did you fix your problem?

[shepd]

I would remove a good transistor from the board and meter it, along with figure out where each pin goes. This would help identify the base, collector, and emitter. After that, I'd assume they're pretty generic transistors and just replace it with one that has the correct pinout.

But you still run some risk doing that. :S

[fpanczel]

Hello All,

I have also problem with small display...
Somebody fix the issue?


BR,
Feri

[lespaulstd]

I am facing the same issue and will try to replace the clock from a donor cluster. In order to test the "new" cluster, can somebody point me the pinout of the connectors to be able to switch it on and see if the clock works?

It is an European Yaris, and part-number is 83800-0D660


That is the one that I have. I just disassembled mine and hooked it up on my test bench to experiment with it. The clock and odometer are a separate assembly from the rest of the instrument cluster. Does anything at all display on the clock area of yours?

50263

Thanks in advance

[GTJos]

Hi all !
Same problem (for over a year now...)
Happy to find this forum/threat. Are there any real solutions yet ? Thank's in advance !

[heinadriaan]

I also have the same problem...

[lespaulstd]

I am facing the same issue and will try to replace the clock from a donor cluster. In order to test the "new" cluster, can somebody point me the pinout of the connectors to be able to switch it on and see if the clock works?

It is an European Yaris, and part-number is 83800-0D660




Thanks in advance

Searching this document (http://www.yarisworld.com/forums/attachment.php?attachmentid=52725&d=1390788430) from this post (http://www.yarisworld.com/forums/showpost.php?p=725529&postcount=10) of CTScott I've been able to check that the donor cluster works.

It is only necessary to connect, pins 1 (12V) and 24 (GND) to power the unit outside of the vehicle. Now my plan is to swap the clock/temperature display of both units.

[Francescocy]

I had the same issue on my 2007 Yaris (got it used on the cheap as my first car and there are some minor issues with it) the ICs in my unit are clearly burnt, they seem to be 6 BJTs or MOSFETs in parallel each with a 22 Ohm resistor to balance load. This part of the circuit seems to provide power to the cathode filaments in the fluorescent display and the parallel design makes it so that if one of the ICs gives up the ghost, the other 5 will follow soon after, since they have to split the load across 5 instead of 6. The clock is not an LCD, but rather a Vacuum Fluorescent Display (VFD), I could't find any information on this specific panel, but in general a voltage of about 2-3V is used on the cathode filaments; I first tried to replace the 6 ICs with a single powerful MOSFET, this kinda worked, but at 12V source to drain and you don't want that going to the filaments! Next step was to cut out the MOSFET and use a buck converter to provide steady 3V DC power. The screen turnes on, but the filament glows dimply orange and the numbers are dimmer than they should; probing the pins with the display on reveals that the anodes are only getting about 2V, if I understand this correctly, they should have a much higher voltage (10-30V), maybe some other part of the circuit is faulty? Another possibility is that the original power circuitry provided a negative bias voltage to the cathode filament respective to the anodes hence why my approach works, but dimly. At this point this is just speculation; I could disassemble the main VFD and probe that, but I'm too afraid of ruining it since I'd like to still be able to see how fast I'm going at the end of all this :)

If any of you has suggestions or can point out things I did wrong, I would be grateful!

[polarcrew]

I have same problem also with 2007 Yaris. I tried to repair solderings on fets and display now lights up and kinda works but fets are damn hot!

I will cotinue to work on issue. If anyone has figured out good fix for this please post some hints!

[sven337]

Might it be 2SB799 transistors? The marking ("MK") is consistent with that.

[sven337]

I solved the problem.
Looks like I was right, these are 2SB799 PNP transistors. I couldn't source them so I bought an equivalent BCX53 reference. I think it even has a somewhat higher nominal current so it should be better than the original ones.
I replaced the 6 transistors with these and everything works perfectly now!

Total time all included around 2h so it's a quick fix too.

My notes on how to disassemble it:
- take out the two side plastic parts (passenger airbag and warning button), these are just plastic clips so pull towards you
- remove the cover of the speedometer by pulling towards you (takes some force)
- remove two screws holding the meter in place
- pull the meter out, you need to rotate/warp the plastic a little
- go back to your desk and remove 2 screws at the back of the unit + the clips
- pull the back of the unit, be careful there is a mirror inside that is going to fall off
- disconnect the "mainboard" (10x10cm board, just pull it out it will disconnect)
- remove 1 screw on the front cover, then remove the front cover (many clips)
- remove the plastic cover of the main display (4 screws + 1 clip + rotate it)
- disconnect the ribbon cable of the main display and note what path it takes
- you can now pull out the power board/main board by removing the two clips and pulling towards you, which will disconnect the clock VFD

change the transistors, do everything in the opposite order, get the champagne out.

[Sumi]

I solved the problem.
Looks like I was right, these are 2SB799 PNP transistors. I couldn't source them so I bought an equivalent BCX53 reference. I think it even has a somewhat higher nominal current so it should be better than the original ones.
I replaced the 6 transistors with these and everything works perfectly now!

Total time all included around 2h so it's a quick fix too.

My notes on how to disassemble it:
- take out the two side plastic parts (passenger airbag and warning button), these are just plastic clips so pull towards you
- remove the cover of the speedometer by pulling towards you (takes some force)
- remove two screws holding the meter in place
- pull the meter out, you need to rotate/warp the plastic a little
- go back to your desk and remove 2 screws at the back of the unit + the clips
- pull the back of the unit, be careful there is a mirror inside that is going to fall off
- disconnect the "mainboard" (10x10cm board, just pull it out it will disconnect)
- remove 1 screw on the front cover, then remove the front cover (many clips)
- remove the plastic cover of the main display (4 screws + 1 clip + rotate it)
- disconnect the ribbon cable of the main display and note what path it takes
- you can now pull out the power board/main board by removing the two clips and pulling towards you, which will disconnect the clock VFD

change the transistors, do everything in the opposite order, get the champagne out.

Could you please help me with the exact transistor needed?

These are the ones that I can source:

BCX 53-16 SMD, PNP, 1A/80V
Frequency: 145MHz
Packaging: SOT89
Collector current: 1A
Collector - emitter voltage: 80V
Power dissipation: 1.35W

OR

BC 869 = BCX 53, PNP, 1A/20V
Frequency: 60MHz
Packaging: SOT89
Collector current: 1A
Collector - emitter voltage: 25V
Power dissipation: 1W

Will any of these work?

Thank you in advance!

[sven337]

Put the champagne back in the bottle if you can, because the repair didn't hold. I haven't disassembled the device again to check what happened, but it sure looks like the transistors died. I do not understand why they would get seriously hot at all, this is a lot of power we're talking about... a display doesn't consume all that much.

Sumi, you want the 80V ones not the 25V ones. The 25V ones aren't BCX53.

[TeeThree]

Hello Sven, I was wondering if you found a solution to the transistors getting hot and burning out?

[sven337]

I do not know why my repair failed. I would assume the transistors are getting hot too, which makes me wonder if maybe the drive circuit is to blame. I wouldn't be able to fix that.
I'm planning to replace these transistors with P-MOSFETs, to see if they behave any better. They should generate less heat.

I've disassembled the clock again, and clearly the transistors were getting hot, and continued to burn off parts of the boards. A bunch of traces were torn apart when I removed the transistors. I've connected P-MOS the best way possible (had to use a few wires where the traces were gone), will test in a few hours and report back. Hopefully MOSFETs will have fewer thermal problems. Next step if *that* fails is to get 2 or 3 big MOSFETs instead of 6 small ones.

I do not have time to test more, but I went with PCP1302 MOSFETs and the result was a very very hot board after 3 minutes of displaying the clock. How much current does that thing pull?!

[sven337]

Just replacing the transistors doesn't seem to work (because they'll die again soon), so let's figure out what they're for exactly and take a higher level look: what is being implemented here?
The way they're connected, the six of them are basically in parallel and drive the cathode (the horizontal filaments) of the VFD. Their job is to get a steady 300mA through these filaments (full brightness, figure empirically found with a bench power supply).

In fact, you can remove the 6 transistors, and connect a constant-current power supply set to 300mA between the + and - (leftmost and rightmost) pins of the VFD, while it's plugged into the board - it will work normally.

I couldn't fully work out how the transistors were driven (=what their base is connected to), but it all goes back to the mainboard and a, on the power board, a pin that seems to be used to dim the VFD. I don't remember it dimming when turning on the headlamps but maybe that's actually what happens. I'm about to lose that feature anyway.

So, instead of trying to fix this broken cheap power supply with such a terrible efficiency that the transistors dissipate multiple watts (about 500mW each, which is not nothing for SOT-89), let's just replace it with something that works better. My theory for why the repair isn't working is that this design relies on the board helping to dissipate some heat, and when it's as badly burnt as mine it doesn't dissipate as well. Of course as soon as 1 transistor dies the rest will follow due to the parallel design. Crappy power supply design that saved maybe 2 bucks.

My plan is to find a buck module with a 2.5V output that I can use as a constant-current device, or if I can, add a series resistor to limit the current to about 300mA.
Then I'll rip out the 6 transistors and connect the buck module where I need it.

[sven337]

OK, this is fixed! Hopefully this time for good.

I had an adjustable MP1584EN-based buck module ("D-Sun" chinese brand).
These super common modules you can find for a few dollars.
For example:
https://www.ebay.fr/itm/Ultra-Small-DC-DC-Step-Down-Power-Supply-3A-MP1584-Adjustable-Replace-LM2596-/322408214136

I used my poor man's lab power supply to test what were the minimal voltage and currents needed to obtain full brightness, and I found out that a constant voltage 1.5V supply would yield a steady 300mA current that would correspond to full brightness. Going to 2.5V would increase current to 450mA without any visible change in brightness, and starting at 4V the filaments would glow red.
(Sorry about the quality of my pictures, I was focused on solving the problem and only took the pics as an afterthought).
https://perso.aquilenet.fr/~sven337/data/yarisclock/test_setup.jpg
https://perso.aquilenet.fr/~sven337/data/yarisclock/halfwatt.jpg
https://perso.aquilenet.fr/~sven337/data/yarisclock/2halfvolt.jpg

Once this was proven working, I cleared some space on the board by removing the transistors and their base and emitter resistors.

https://perso.aquilenet.fr/~sven337/data/yarisclock/cleanboard.jpg

Laid out a layer of tape to insulate, soldered the module and taped it in place. This fits with room to spare when reassembling everything.
https://perso.aquilenet.fr/~sven337/data/yarisclock/final.jpg

Sorry that final picture is so anti-climactic.. Everything works quite well for now. I hope it lasts, this time, but see no reason why it wouldn't.

[TeeThree]

Thanks for the feedback Sven. I'm confident you may have found a lasting solution to the problem. I will look into the DC-DC converter - a nice neat solution.
Would something like the old LM317 work as well? I already have that in my box of spare parts.
If i set the LM317 to 1.5v this should be ok from what you have discovered from measurements.
Thank you for your effort and feedback.

[Kaanktm]

OK, this is fixed! Hopefully this time for good.

I had an adjustable MP1584EN-based buck module ("D-Sun" chinese brand).
These super common modules you can find for a few dollars.
For example:
https://www.ebay.fr/itm/Ultra-Small-DC-DC-Step-Down-Power-Supply-3A-MP1584-Adjustable-Replace-LM2596-/322408214136

I used my poor man's lab power supply to test what were the minimal voltage and currents needed to obtain full brightness, and I found out that a constant voltage 1.5V supply would yield a steady 300mA current that would correspond to full brightness. Going to 2.5V would increase current to 450mA without any visible change in brightness, and starting at 4V the filaments would glow red.
(Sorry about the quality of my pictures, I was focused on solving the problem and only took the pics as an afterthought).
https://perso.aquilenet.fr/~sven337/data/yarisclock/test_setup.jpg
https://perso.aquilenet.fr/~sven337/data/yarisclock/halfwatt.jpg
https://perso.aquilenet.fr/~sven337/data/yarisclock/2halfvolt.jpg

Once this was proven working, I cleared some space on the board by removing the transistors and their base and emitter resistors.

https://perso.aquilenet.fr/~sven337/data/yarisclock/cleanboard.jpg

Laid out a layer of tape to insulate, soldered the module and taped it in place. This fits with room to spare when reassembling everything.
https://perso.aquilenet.fr/~sven337/data/yarisclock/final.jpg

Sorry that final picture is so anti-climactic.. Everything works quite well for now. I hope it lasts, this time, but see no reason why it wouldn't.


Hi, thank you for sharing this. It is really helpful. Hope it lasts lifelong. :)

Could you please inform about the circuit connections on the board. I’m not bad with electronics but apparently not as good as you. Also i couldn’t find about detailed module connection schematics.

So i will appreciate and be very grateful for your reply. Thanks again. This forum rocks. :)

[sven337]

Would something like the old LM317 work as well? I already have that in my box of spare parts.
If i set the LM317 to 1.5v this should be ok from what you have discovered from measurements.


Electrically it will work. Thermally I'm not so sure. LM317 is a linear regulator so in order to deliver 300mA@1.5V it will draw 300mA@12V and dissipate the difference, which is 3.1W.
The TO220 LM317 datasheet mentions a thermal resistance of about 40°C/W, so you're looking at 120°C over ambient temperature for a device with a maximum operating temperature of 125°C. That's why the original board had 6 transistors...
I wouldn't attempt it. A buck regulator has a better efficiency.
The LM317 is supposed to have thermal protection so it will likely shut down without burning too many things, but if your board is like mine any heat is too much heat.

[sven337]

Could you please inform about the circuit connections on the board.

Are you asking about how to connect the buck module I had to the board? Assuming you have the same, but all buck modules work the same way anyway, you have three leads to connect: Vin, Vout, and GND.
If you look at my very blurry (sorry..) last picture, you can see two red wires and one black wire (at the bottom)*come out of the module. The black wire is GND, and I've taken it at the GND of the capacitor that is next to the blue inductor.
Vin was the + of this capacitor (I think the capacitor/inductor/diode here are an input filter, all I really care about is that there's a constant 12V power supply available there and it was the input of the NPN transistors).
Vout is the leftmost pin of the VFD connector (all 4 left pins are connected together).
I hope this helps you

[Kaanktm]

Are you asking about how to connect the buck module I had to the board? Assuming you have the same, but all buck modules work the same way anyway, you have three leads to connect: Vin, Vout, and GND.
If you look at my very blurry (sorry..) last picture, you can see two red wires and one black wire (at the bottom)*come out of the module. The black wire is GND, and I've taken it at the GND of the capacitor that is next to the blue inductor.
Vin was the + of this capacitor (I think the capacitor/inductor/diode here are an input filter, all I really care about is that there's a constant 12V power supply available there and it was the input of the NPN transistors).
Vout is the leftmost pin of the VFD connector (all 4 left pins are connected together).
I hope this helps you

Actually i was quite able to clear up my mind after asking the question. With your answer it is now crystal clear. Thank you so much again. Hope it would last long.

[adsb]

Has this repair held out for you so far sven337 ?

[sven337]

Because I got the question in private multiple times:
- buck modules are not insulated so they have a single ground - no need to connect both ground wires, any of the two will do
- yes, the repair is still holding out, and I've got a good hope that it will hold forever because I think it's "clean"

Do note that you need to remove the transistors (and while you're at it the emitter and base resistors to make room) before connecting the buck module.

[adsb]

Thanks sven337,

So the wiring is like this



The 12v feed to the module derived from smd capacitor c535 (470uf/25v) and the dc, aprox 1.5v out (adjust via potentiometer) goes to the left hand pin 1 of the VFD.

Many Thanks again for your help.

[sven337]

Correct

[Kaanktm]

Did it yesterday works perfect for now. Thanks again. Btw, be sure that frame of VFD which is the white plastic part, is holding it. There are small guides on it, mine was broken by the one who disassembled it before i guess. Because after i did everything it just worked but when i put it together it stopped working.

Then i just disassembled again and stick the VFD to white plastic frame, now it is perfect.

[sven337]

That is correct, my instructions didn't cover it but the VFD is held in place inside the white plastic part by its top, you have to slide the top first and then press down the part with the pins to get it back in the white plastic part.
But, you don't actually need to remove the VFD from the white plastic part for this fix, what you need to do is separate the white plastic part from the board which my instructions do cover, albeit without drawing attention to the need to ensure that the VFD pins are correctly connected upon reassembly (it's just a matter of pressing hard on the VFD itself).

[adsb]

Hi all,
I have the buck module on route from China and hope to complete this modification/repair in the next few weeks.
Can someone explain what this fragile VFD white plastic frame looks like.
I take it that we are dealing with the small VFD and is this "frame" part is the frame which holds the whole clock/warning light pcb to the rest of the instrument assembly ? Hence "many clips" in svens dis assembly guide.
I am looking on this thread for a photo of the frame to identify it but all i can see is a small black frame /surround fitted to the small clock VFD.
Thanks guys.

Great fix btw !

[sven337]

Don't worry about it. Can't miss it when you disassemble, it's the largest plastic part and the only one colored white. And there's nothing to be careful about really, just to know that when you separate it from the black part at its back, it will disconnect the VFD, so don't pull sideways. And after you clip the black part back on (don't push sideways...), you'll need to push on the VFD (it's glass, you can push hard) to make sure its pins are connected.

[adsb]

Thanks sven337, I see the white part now, it is pictured in post #48 of this thread, it looks like a support frame to hold the main pcb board.
From the descriptions the white frame holds the VFD display module and the main pcb and when you separate the frame from the main PCB the VFD stays in place on the white frame as it has a slot and a pair of clips to hold the VFD module.
Then its a case of unclipping the VFD from the frame and plugging it into the bare socket for testing/wiring up. Plugging in the VFD provides a load so that the buck module output voltage can be adjusted properly (with a load attached).
I take that the buck output wire is stripped back a few mm at the VFD socket end and the bare end is pushed into pin #1 of the socket receptacle? (The male pin of the VFD holds the wire in place when the VFD is placed back onto the white frame and its all pushed back together).

Did you have any diffculty in removing the SMD components ? Lead free solder is a pain sometimes.

I can see this as a really good fix as the MP1584 based modules run at much lower temperatures than others. :thumbsup:

Still waiting for my package from China (buck module)

[sven337]

It's a buck module, not a linear power supply, you can adjust it without a load.
The VFD is only useful for testing, if you're doing my repair you don't need it you just need to set up the buck module for about 1.5V.

Removing the SMT components is easy. Chisel tip, 30W or more, add a bunch of leaded solder, heat up like crazy (you don't care you're removing everything) and the transistors will slide right off.

As for the VFD socket, I actually soldered the output lead of the buck module to the base of the VFD connector. Not soldering sounded like a potential issue with vibration.

[adsb]

Right hand drive model repaired, thanks to sven337 for the instructions.

Photos of MP1584EN device, testing with DMM to obtain correct output of 1.5v, more photos of the existing transistors and after removal (a few pads came off in the process) , close ups of buck regulator in situ and wiring to pin 1 of VFD connector.

I disconnected the battery negative terminal before removing cluster.
Used a 12v 1.2ah battery from commercial intruder alarm panel as poor mans lab psu for testing.

I noted that there were 5 transistors not 6 for my model.
That ribbon cable is a right PITA to get back in to the slot and close the latch on the connector !

Sorry if the photos are in the incorrect order.

Thanks again sven337 !

[sven337]

Thank you for the excellent pictures that will, no doubt, help people implement the fix.

[NOLF]

Sorry but i can find dashboard pinout, can you post it for me. I can't test me dash, i don't no where is positive and negative.

[sven337]

https://perso.aquilenet.fr/~sven337/data/yarisclock/test_setup.jpg
+12V top right
GND bottom left

[sven337]

Someone asked me to repair their clock, I took a better picture of the fix + the test setup.

[Sumi]

Is there anyone out there who managed to fix it by replacing the transistors? I'd need the dimming feature.

[Sumi]

Okay, so I've pulled it apart today and resoldered the transistors, as mentioned by a comment on sven337's page. I don't know if this will last, because when I start the car the clock display comes on pretty slowly, which tells me that something isn't quite right, although I don't remember how it used to be. But at least it works for now.

@sven337, do you think that there is any risk of fire when the transistors die? I can imagine there is quite some heat if it's enough to make the PCB turn brown on the other side.

[worm6666]

Hi folks.

I have another option - after successful measuring of all transistors - all were good - I cleaned the paths and returned back originals... And it works again.

And have created a cooling pad - from aluminium piece of thin sheet connected with heat conductive paste to transistors - like for pc repairs :smile:

https://i.imgur.com/Cj5HktQ.jpg

https://i.imgur.com/HAyucGD.jpg

https://i.imgur.com/bD2SxvQ.jpg

https://i.imgur.com/kpmaEJl.jpg

https://i.imgur.com/0hXdnFW.jpg

hope it helps somebody... :smile: :thumbsup: :headbang:

It looks like only the soldering under the marked 3 transistors were burned...

[bubinio]

Hi guys,

I tried sven337 solution but with 1,5V the clock is not bright at all. When i adjust it at about 2,7V to be brighter then the red lines appear. When the lights are turned on, the clock is not readable!

Great work though for sven337 and all the rest!!

[Sumi]

Okay, so I've pulled it apart today and resoldered the transistors, as mentioned by a comment on sven337's page. I don't know if this will last, because when I start the car the clock display comes on pretty slowly, which tells me that something isn't quite right, although I don't remember how it used to be. But at least it works for now.

@sven337, do you think that there is any risk of fire when the transistors die? I can imagine there is quite some heat if it's enough to make the PCB turn brown on the other side.

Died today again.

Any ideas how to do the boost converter mod with retaining the dimming feature?

[krume]

Hi folks.

I have another option - after successful measuring of all transistors - all were good - I cleaned the paths and returned back originals... And it works again.

And have created a cooling pad - from aluminium piece of thin sheet connected with heat conductive paste to transistors - like for pc repairs :smile:

https://i.imgur.com/Cj5HktQ.jpg

https://i.imgur.com/HAyucGD.jpg

https://i.imgur.com/bD2SxvQ.jpg

https://i.imgur.com/kpmaEJl.jpg

https://i.imgur.com/0hXdnFW.jpg

hope it helps somebody... :smile: :thumbsup: :headbang:

It looks like only the soldering under the marked 3 transistors were burned...

Hi worm6666, I like Your solution, I would put even more robust heatsink. Is it working still?

[krume]

Hi guys,

I will try worm6666 solution and update here for result.

[worm6666]

I have made some modification - the GLUE-GUN version was not good - it was falling apart after heating itself from transistors - also I have made some steel clips (from paper-clips) covered with thermal shrinking tubes (to prevent shorts)... easy solution holding all parts together also on higher temperatures...

https://i.imgur.com/8a0eYqe.jpeg

- and like You can see - under whole heatsink is thermal-conducting pad (Aliexpress buy) :-)

[krume]

Like!

[krume]

I think I fix it for good.
Changed transistors with more powerful one, I used 2SB1516, any PNP 1A, 1~2W would do. Used thermal conducting material and aluminum heatsink from some old motherboard, paper clips to fix everything.
I will update if it is not fixed for good.

[dreamer]

Hello,
As others on this thread, I have the clock/temperature/ average consumption display problem.
The thing is that I just bought the car second hand 2 weeks ago. I didn't see that missing display until I drived it several days, asking myslef how possible it was for a car not to have a clock ( I use to have the Yaris 2004 before, that has all those features)
The person that sold it to me ( herself 2nd byuer) said that she never paid attention to that and that it was surely already out when she bought the car 5 years ago ).

Anyway, I've found this thread via the french page of sven.
The problem is Im not equiped (and talented) to start trying taking all those pieces out :/
I saw on the thread that you can find the full part with the screen etc but it is 150 € !

My questions are :
- is there a way to find just the electronic panel , cheap, and to replace it ?
- how expensive would it cost to me if I go to a toyota garage and ask them to repair it ?

Also, if you know someone in Belgium that would accept to do the work for me in exchange of of a good price, Im interested :)

Oh, and I also have the "turning button" to change from outside/recycling air" that is blocked on the " outside air" , but I hope it is just a plastic thingy blocked behind the n panel, nothing electronic here)

Thanks a lot !

Regards,
Dreamer

[mimik]

Is it possible to replace the old faulty cluster with a second hand unit that works?
Or will that mess up ODO etc?

[almamater]

Well, my Yaris 2006 had the same issue 1 month ago, yesterday i decided to do the procedure mentioned here, thanks to Sven337 !!

All worked Now, i decided not to remove the transistors, i just added the MP1584EN, and in this way, the dim functionality continues to work..

If anyone needs pictures i can post them, i took some.

Thanks!

[brugal67]

could you send me the photos of the modification?

[Marafado]

Well, my Yaris 2006 had the same issue 1 month ago, yesterday i decided to do the procedure mentioned here, thanks to Sven337 !!

All worked Now, i decided not to remove the transistors, i just added the MP1584EN, and in this way, the dim functionality continues to work..

If anyone needs pictures i can post them, i took some.

Thanks!

Hello.
Another one with the same problem.
Thanks to sven337's posts, I'll try to follow his procedures as well.
In your case, you decided not to remove the transistors. You say that this way the variable brightness functionality remained functional.
Can you confirm that everything is back to normal after the repair and no more problems have appeared?
I'm thinking of a more complex repair, but just in case it's justified!

Thanks

[Marafado]

Here is the solution I implemented.

[bubinio]

Here is the solution I implemented.

Hi mate! Can you give more details about the module?

[FabioB]

C'è qualcuno che potrebbe dirmi se ho dissaldato i giusti cluster? Grazie

https://ibb.co/PvPWccxF

[jacki22]

Please, I'm looking for the wiring diagram for the connector.