Update to adding trans temp gauge...
- Thread starter DougAMiller
- Start date
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yes, you are correct. I was mistaken. The code is likely not in the top two lines of code. The service brake booster nag came back after a few days. I wish it would go away again!
OP
OP
DougAMiller
Full Access Member
I don't know where the brake booster config is stored, but it doesn't seem to me that they would put it in the cluster. To me it would make more sense for that to be stored in the either the ABS, BCM or PCM module. I would guess that it will require reprogramming one of those.
Your tire size & axle ratio make a final drive ratio for two computers in your truck. ABS and PCM.
The ABS cal is important but not the only piece of the puzzle. A Tech2 can change the ABS tire size calibration but not the final drive ratio in the PCM. I'm not sure you can use the Tech 2 to re-calibrate the ABS controller for a different axle ratio. Likely you can do at least the ABS tire size calibration with some of the high end Autel and SnapOn diag tools but do your own research.
The PCM handles calibration of vehicle speed data to the instrument panel over the GM Class II Serial databuss. You'll need to use a tuner package to directly program the PCM or a modified Cal file from GM to program the PCM over AC Delco TIS web. Good luck getting a modified Cal file from GM even if you're a dealership. I used HP Tuners to change from 245/75R16 to 265/70R17 tires on my 2005 K2500HD. Supposedly some of the handheld tuners can modify this PCM parameter.
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Jeffescortlx has several 2nd gen GMT800 cluster repair videos up. More than one shows a proper needle sweep using a Tech 2 on his bench.
https://www.youtube.com/channel/UCzJWy4r_V89YYt4GBxNaJfQ
alaska_guy
Full Access Member
You can remove the brake booster message by shorting the two outer pins on the connector. I did this on my suburban.
alaska_guy
Full Access Member
Hp tuners will allow you to fix the axle ratio and brake booster message. If I had my suburban still I would of been able to tell you what two wires to tie together to get rid of that message. It's looking for a normally closed circuit.
Logan5
Full Access Member
Want to say thanks to OP for great info and report successfully adding Trans Temp gauge to my 05 Tahoe.
Only difference was the trans temp hex was '03' and needed to be changed to '42' which I found in some YT vids.
I ended up using:
and
Only difference was the trans temp hex was '03' and needed to be changed to '42' which I found in some YT vids.
I ended up using:
and
Chironal 2set SOIC8 SOP8 Welding Wire +2pcs Board Test Clip+ Two Boards for EEPROM 93CXX/25CXX/24CXX in Circuit Programming on USB Programmer TL866CS TL866A EZP2010 (2Pcs Board): Amazon.com: Industrial & Scientific
Chironal 2set SOIC8 SOP8 Welding Wire +2pcs Board Test Clip+ Two Boards for EEPROM 93CXX/25CXX/24CXX in Circuit Programming on USB Programmer TL866CS TL866A EZP2010 (2Pcs Board): Amazon.com: Industrial & Scientific
www.amazon.com
Ilikemtb999
Full Access Member
Did you use the provided software?
Logan5
Full Access Member
No I have a Mac, and the provided software was Windows only. I ended up using:
David Griffith / minipro · GitLab
An open source program for controlling the MiniPRO TL866xx series of chip programmers
gitlab.com
Which looked hard but was surprisingly easy.
