DIY Gauge

[dj92]

Hi there,
some days ago, I've completed my LCD gauge using a GLCD, an Arduino pro mini, a generic ELM OBD adapter (with BT) and a bluetooth master which connects to the adapter's BT module :)
Overall cost was far less than 50€.

http://files.brauchmer.net/imghost/up/small_fbd15818f9bd03d9d246cefa82e850cc.jpg (http://files.brauchmer.net/imghost/up/fbd15818f9bd03d9d246cefa82e850cc.jpg)

http://files.brauchmer.net/imghost/up/small_c7eed6540f087453c86c6f34cf9d9758.jpg (http://files.brauchmer.net/imghost/up/c7eed6540f087453c86c6f34cf9d9758.jpg)

Sadly the green has the usual yellowish tint in reality unlike in the pictures.
1st world problems :laugh:

When I turn on IGN, the bluetooth module looks for the adapter's and establishes a connection.

http://files.brauchmer.net/imghost/up/small_39db6f71e8b5f34f941d8abf3c6f2b86.jpg (http://files.brauchmer.net/imghost/up/39db6f71e8b5f34f941d8abf3c6f2b86.jpg)

Then, the arduino sees a wired-like connection to the ELM where it sends queries to.

If it gets an answer, the "init"-loop is quit and the usual operation begins:

http://files.brauchmer.net/imghost/up/small_c0db275280374ec838911f76ef0c211c.jpg (http://files.brauchmer.net/imghost/up/c0db275280374ec838911f76ef0c211c.jpg)

And when I start the engine:
http://files.brauchmer.net/imghost/up/small_2379cfa7fce9571820f12740e2361f16.jpg (http://files.brauchmer.net/imghost/up/2379cfa7fce9571820f12740e2361f16.jpg)
Attention, it really reads "C[oo]L[a]NT" at 2 o' clock :biggrin:

I've decided against adding more values because of the rather small display area and the fact that the ELM-clone runs just at 4MHz and is rather slow because of that.
By now, the responsiveness is acceptable.
The values are aligned at te left end, so they don't woggle too much if they change between values (e.g. the RPM).

For the next generation, I've got already a module with a PIC32 @80MHz in the drawer that I'm going to hook up to the CAN directly.
Because I'm not limited to OBD requests, I can passively get parameters flying around on the bus - including a (IMHO) quite accurate value for the injected fuel amount.
Upon request, I can post the rather ugly (but working fine) code, the schematics are so easy I haven't made a plan.

[Yesitisyaris]

Looking at getting one of these for my yaris a scangauge have anybody used one of these?

[dj92]

I did not because it's far too expensive imao.
It just estimates the fuel amount using MAP, MAF and AFR, right?
(As far as I know, the 1KR-FE does not measure the MAF, at least I could not find it neither with Torque nor with Techstream)

[CTScott]

I did not because it's far too expensive imao.
It just estimates the fuel amount using MAP, MAF and AFR, right?
(As far as I know, the 1KR-FE does not measure the MAF, at least I could not find it neither with Torque nor with Techstream)

The ScanGauge is very handy for the non-DIY Engineer type. I too created my own gauge, which has far more functionality than the ScanGauge, but many hundreds of hours of development time makes it far more expensive than the $150 for a ScanGauge II.


Your 1KR-FE uses a MAP, rather than MAF sensor.

[CrankyOldMan]

Wow, that's a really nice setup! I've played with Arduinos at school, and have seen a few people use BT communications.

I've got a scangauge II and it's a very useful tool. It can monitor anything on the OBD-II diagnostics bus, plus anything that you "find" the OEM codes for. It also reads and clears diagnostic trouble codes (DTC)/check engine light (CEL) errors, can record performance data (0-60, 1/4 mile, etc), and a few other neat things that are escaping me at the moment.

[dj92]

I've played with Arduinos at school, and have seen a few people use BT communications.
Not so old, huh? :biggrin:

I have been thinking about adding an automatic contrast compensation (I have to correct it when the interior and the display have reached a higher temperature, otherwise it gets all black), sadly this will be a bit tricky because it is a negative voltage :/

[CrankyOldMan]

Not so old, huh? :biggrin:

I have been thinking about adding an automatic contrast compensation (I have to correct it when the interior and the display have reached a higher temperature, otherwise it gets all black), sadly this will be a bit tricky because it is a negative voltage :/

Ahem, University. :smile:

You may be better off finding an "extended temperature range" version of that display.

[dj92]

That'd be of course better, but this was another "low budget" project, I got 4 of these displays for free.
It's not forever, I've already been thinking about buying another instrument and replacing the side VFD by a graphic one.
Or I'll take an OLED and add a colour filter...
But before, I'll extend the CAN bus ;)
Pictures will follow as soon as it's worth taking them^^

[CTScott]

That'd be of course better, but this was another "low budget" project, I got 4 of these displays for free.
It's not forever, I've already been thinking about buying another instrument and replacing the side VFD by a graphic one.
Or I'll take an OLED and add a colour filter...
But before, I'll extend the CAN bus ;)
Pictures will follow as soon as it's worth taking them^^

I used an OLED for mine and replaced the VFD clock on the left side of the non-tach US cluster. The color OLED that I used was about $80. I had a lot of issues with sunlight readability with everything else that I experimented with. Here's a video of mine from a while back:

https://www.youtube.com/watch?v=ZvQ68qXN39w

[dj92]

https://www.youtube.com/watch?v=ZvQ68qXN39w
Looks really nice!
I've got some OLEDs at hand, too, sadly each one of them is mounted on a rather clumsy PCB.
These monochrome 128*64 OLEDs are available for a reasonable price, sadly they're quite small.

[japle]

I use my note 10.1 as a gauge, with the app called torque. The bluetooth adapter was puechased from ebay

[Yesitisyaris]

Thank you for the your reply. I think I will get one of these as it would be neat to keep track of the info it gathers. Thanks again