Toyota Yaris Forums - Ultimate Yaris Enthusiast Site
 

 


 
Go Back   Toyota Yaris Forums - Ultimate Yaris Enthusiast Site > Technical Forums > DIY / Maintenance / Service
  The Tire Rack

Reply
 
Thread Tools Display Modes
Old 11-28-2008, 11:37 PM   #37
Yarice
 
Yarice's Avatar
 
Drives: 2008 LB Meteoric Metallic
Join Date: Oct 2008
Location: Victorville, CA
Posts: 200
Mines an 2008 3dr LB
Yarice is offline   Reply With Quote
Old 11-28-2008, 11:47 PM   #38
Yarice
 
Yarice's Avatar
 
Drives: 2008 LB Meteoric Metallic
Join Date: Oct 2008
Location: Victorville, CA
Posts: 200
Ive done this 3 times and im not gonna move the car till tomorrow and let the car sit overnight if thats gonna make a difference, if not im gonna put everything back the way it was.
Yarice is offline   Reply With Quote
Old 11-29-2008, 01:00 AM   #39
CTScott
ULTIMATE
 
CTScott's Avatar
 
Drives: 09 5dr LB, 2x 08 3dr LB
Join Date: Oct 2008
Location: USA, CT
Posts: 13,455
OK. Linny just PM'd me. His had been working fine until he headed out of town for Thanksgiving. All of his trips prior had been short (<6 miles). About 15 minutes into his trip the light came on.

So, it looks like this solution does not work - It looks like the third component is time.
CTScott is offline   Reply With Quote
Old 11-29-2008, 02:02 AM   #40
CTScott
ULTIMATE
 
CTScott's Avatar
 
Drives: 09 5dr LB, 2x 08 3dr LB
Join Date: Oct 2008
Location: USA, CT
Posts: 13,455
Quote:
Originally Posted by CTScott View Post
OK. Linny just PM'd me. His had been working fine until he headed out of town for Thanksgiving. All of his trips prior had been short (<6 miles). About 15 minutes into his trip the light came on.

So, it looks like this solution does not work - It looks like the third component is time.
Looked into it a bit more. The TPMS starts a timer once it receives power. After ~15 minutes of power and no comm from the sensors it turns the light on.

I am now experimenting with just using the brown wire, which is the output to the combination meter. To turn the light off, the TPWS module supplies ~4.0V to the brown wire. At 2.4V or less the light will come on.

I disconnected the TPWS and applied ~4.0 V to the brown wire (via a resistor voltage divider from the 12V supply on the connector). The light does not light. I will drive around for a week or so to make sure that eliminating the module doesn't cause a DTC to be thrown.
CTScott is offline   Reply With Quote
Old 11-29-2008, 02:29 PM   #41
ivanmadeline
 
ivanmadeline's Avatar
 
Drives: 2008 Yaris (Sedan)
Join Date: Oct 2008
Location: NC
Posts: 61
Thanks for the help.
ivanmadeline is offline   Reply With Quote
Old 11-29-2008, 02:37 PM   #42
CTScott
ULTIMATE
 
CTScott's Avatar
 
Drives: 09 5dr LB, 2x 08 3dr LB
Join Date: Oct 2008
Location: USA, CT
Posts: 13,455
Quote:
Originally Posted by CTScott View Post
Looked into it a bit more. The TPMS starts a timer once it receives power. After ~15 minutes of power and no comm from the sensors it turns the light on.

I am now experimenting with just using the brown wire, which is the output to the combination meter. To turn the light off, the TPWS module supplies ~4.0V to the brown wire. At 2.4V or less the light will come on.

I disconnected the TPWS and applied ~4.0 V to the brown wire (via a resistor voltage divider from the 12V supply on the connector). The light does not light. I will drive around for a week or so to make sure that eliminating the module doesn't cause a DTC to be thrown.

OK. I've been driving around today with the TPWS disconnected as above, and no TPWS light. We are going out to dinner tonight, and where we are going is about 35 minutes away, so that will be a good test. If the light remains off and I still don't have any DTCs logged, when I get home tonight I'll post the updated method.
CTScott is offline   Reply With Quote
Old 11-29-2008, 02:38 PM   #43
Yarice
 
Yarice's Avatar
 
Drives: 2008 LB Meteoric Metallic
Join Date: Oct 2008
Location: Victorville, CA
Posts: 200
Sweet, thanxs for the update, were all waiting to see how it goes.
Yarice is offline   Reply With Quote
Old 11-29-2008, 03:16 PM   #44
blacksandiegovitz
Your mom goes to college
 
blacksandiegovitz's Avatar
 
Drives: 08 Vitz
Join Date: Oct 2008
Location: Just chillin' out brah !
Posts: 1,436
damn , so this doesn't work ???? good thing I didnt go cutting wires . Im just gonna have my sensors installed on my racingharts when I get them powder coated .
blacksandiegovitz is offline   Reply With Quote
Old 11-30-2008, 01:37 AM   #45
CTScott
ULTIMATE
 
CTScott's Avatar
 
Drives: 09 5dr LB, 2x 08 3dr LB
Join Date: Oct 2008
Location: USA, CT
Posts: 13,455
Quote:
Originally Posted by CTScott View Post
OK. I've been driving around today with the TPWS disconnected as above, and no TPWS light. We are going out to dinner tonight, and where we are going is about 35 minutes away, so that will be a good test. If the light remains off and I still don't have any DTCs logged, when I get home tonight I'll post the updated method.
OK. The new solution looks good. After a bunch of short trips and a 30 minute each way dinner run, no TPWS light and no logged DTCs. The new solution goes as follows (and does not require the system to have been light-free prior):

This procedure requires some minor soldering and can be done with or without a switch to re-enable the TPWS.

1. Make a simple voltage divider to provide ~4 Volts to the TPWS light input to the Combination meter.



Parts Required:
3 150 ohm resistors (radio shack part # 271-1109 for a 5 pack)
22 AWG Wire (Red, Black, green (also yellow and blue if using switch)
Switch(optional), SPDT toggle or push on/off (Radio Shack part # 275-1555)
Heat shrink tubing or electrical tape
18-22 AWG (red) tap-splice connectors (3 for no switch, 4 for switch)

a. Solder three 150 ohm resistors end to end.
b. Solder a 6" piece of black wire to one end and a 6" piece of red wire to the opposite end of the string of resistors.
c. Solder a 6" piece of green wire between the first and second resistor from the black wire end.



d. Cover the resistors with heat shrink tubing or electrical tape.



e. Skip to step 2 if not adding a switch.
f. Solder a 6" piece yellow wire to the center terminal of the switch
g. Solder a 6" piece of blue wire to one of the end terminals of the switch.
h. Solder the free end of the green wire to the other end terminal of the switch.



i. Cover the exposed switch terminals with heat shrink tubing or electrical tape.




2. With the car powered off, unplug the TPWS module connector
3. Clip the brown wire (leave a couple of inches so you can reconnect later if so desired)



4. Using a tap splice, connect the red wire to the red wire on pin 7 (This red is next to an empty spot at position 8 {RED, empty, white, white, grey, black})
5. Using a tap splice, connect the black wire to white wire on pin 9 (Next to the empty spot after the red wire {red, empty, WHITE, white, grey, black})



6. If not using a switch, connect the green wire to the brown wire which goes to the combination meter (not the connector end of the cut wire).
7. If using the switch, connect the blue wire to the brown wire which goes to the combination meter (not the connector end of the cut wire).
8. If using the switch, connect the yellow wire to the other end of the brown wire, which is attached to the connector.
9. If not using the switch, leave the TPWS connector off. If using the switch, plug the connector into the TPWS.
10. Turn on the ignition. If not using the switch, the TPWS light should be off.
11. If using the switch and the TPWS light is on, press the switch and the light should turn off.

Last edited by CTScott; 12-02-2008 at 01:04 AM. Reason: Revised resistor value
CTScott is offline   Reply With Quote
Old 11-30-2008, 01:53 AM   #46
eTiMaGo
vroom vroom
 
eTiMaGo's Avatar
 
Drives: lil red 5-door
Join Date: Sep 2006
Location: Bangkok, Thailand
Posts: 7,712
Send a message via AIM to eTiMaGo Send a message via MSN to eTiMaGo Send a message via Yahoo to eTiMaGo Send a message via Skype™ to eTiMaGo
interesting... One thing I am curious about, what kind of signal do the sensors give out? Is it just a binary "too low/good" signal or an actual value representing the pressure for each wheel? If it's the second case, it would be quite cool to hack those signals into an actual per-wheel pressure display!
__________________
The price of freedom of religion, or of speech, or of the press, is that we must put up with a good deal of rubbish.
- Robert Jackson


Bye bye 1NZ...
eTiMaGo is offline   Reply With Quote
Old 11-30-2008, 02:14 AM   #47
CTScott
ULTIMATE
 
CTScott's Avatar
 
Drives: 09 5dr LB, 2x 08 3dr LB
Join Date: Oct 2008
Location: USA, CT
Posts: 13,455
Quote:
Originally Posted by eTiMaGo View Post
interesting... One thing I am curious about, what kind of signal do the sensors give out? Is it just a binary "too low/good" signal or an actual value representing the pressure for each wheel? If it's the second case, it would be quite cool to hack those signals into an actual per-wheel pressure display!
The sensors transmit a packet with their ID, pressure, and temperature. Hacking the protocol would be an interesting project...
CTScott is offline   Reply With Quote
Old 11-30-2008, 11:16 AM   #48
linny
 
Drives: '08 liftback mt
Join Date: Nov 2008
Location: Mn
Posts: 39
Thank you for putting so much effort into this modification CTSCOTT. I will make a trip to Radio Shack when they open this morning!
linny is offline   Reply With Quote
Old 11-30-2008, 11:30 AM   #49
CTScott
ULTIMATE
 
CTScott's Avatar
 
Drives: 09 5dr LB, 2x 08 3dr LB
Join Date: Oct 2008
Location: USA, CT
Posts: 13,455
Quote:
Originally Posted by linny View Post
Thank you for putting so much effort into this modification CTSCOTT. I will make a trip to Radio Shack when they open this morning!
I realize that this solution is a bit more work than the original cut two wires one, so if anyone needs to do this and doesn't have the equipment, etc. to solder it up, I can make it up and ship it as a nice little kit.
CTScott is offline   Reply With Quote
Old 11-30-2008, 02:25 PM   #50
ivanmadeline
 
ivanmadeline's Avatar
 
Drives: 2008 Yaris (Sedan)
Join Date: Oct 2008
Location: NC
Posts: 61
Thanks for all the work CTSCOTT I just got back from Radio Shack with all the items. I hope that this time it all works.
ivanmadeline is offline   Reply With Quote
Old 11-30-2008, 02:43 PM   #51
Chupacabra
Banned
 
Drives: 2009 Yaris liftback
Join Date: Nov 2008
Location: CT
Posts: 350
awesome write-up Scott!
Chupacabra is offline   Reply With Quote
Old 11-30-2008, 03:13 PM   #52
blacksandiegovitz
Your mom goes to college
 
blacksandiegovitz's Avatar
 
Drives: 08 Vitz
Join Date: Oct 2008
Location: Just chillin' out brah !
Posts: 1,436
Yes , you got it too work , thats great ! Thanks for doing the research/testing for this fix . I'll be doing this within the next couple days , im so over that damn light in the dash.
blacksandiegovitz is offline   Reply With Quote
Old 12-02-2008, 01:09 AM   #53
CTScott
ULTIMATE
 
CTScott's Avatar
 
Drives: 09 5dr LB, 2x 08 3dr LB
Join Date: Oct 2008
Location: USA, CT
Posts: 13,455
Please look at the directons on page 3. Based on feedback of mixed results, I changed the resistor value as the original value was causing a valtage drop that put it on the edge, where it would work on some cars and not on others.
CTScott is offline   Reply With Quote
Old 12-02-2008, 09:26 PM   #54
ivanmadeline
 
ivanmadeline's Avatar
 
Drives: 2008 Yaris (Sedan)
Join Date: Oct 2008
Location: NC
Posts: 61
Quote:
Originally Posted by CTScott View Post
Please look at the directons on page 3. Based on feedback of mixed results, I changed the resistor value as the original value was causing a valtage drop that put it on the edge, where it would work on some cars and not on others.
I tried doin it on Sunday but the problem I had was that when I hit the button the light would start flashing the it would come on then I hit the button again and the same thing it would just flash for a few minutes and then stay on again.
I dont know if this makes a difference but i Dont have a brown cable on mine I have a white with a black stripe were that brown one is on your write up. Any suggetions. thanks for all your help.
ivanmadeline is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Tire pressure sensors Tink1 Wheels, Tires and Suspension Forum sponsored by The Tire Rack 11 10-21-2008 05:53 PM
Intake Systems Decision Maker.. Blenjar Performance Modifications 25 09-15-2007 10:07 PM
The Tire inflation debate... Tankota General Yaris / Vitz Discussion 20 06-01-2006 07:09 PM


All times are GMT -4. The time now is 09:35 PM.




YarisWorld
Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.