Results 1 to 6 of 6

Thread: Can only write to p12 ecu with bench tester but not in truck

  1. #1
    Tuner in Training
    Join Date
    Feb 2024
    Posts
    15

    Can only write to p12 ecu with bench tester but not in truck

    So I have a 2006 trailblazer making some very small tweaks to. When I try and write in the truck it times out. If I take the pcm out and use a bench tester I can write works fine. How do I go about fixing this? Do a full system scan with a scan tool not dtcs in any sytem. I can read in truck. I can watch data in truck. Just cant write.

    Home made set up very proud of myself that this worked.20240301_135332.jpg
    Last edited by Fuse; 03-02-2024 at 10:09 PM.

  2. #2
    Tuning Addict blindsquirrel's Avatar
    Join Date
    Apr 2017
    Location
    Meridian MS
    Posts
    7,644
    What brand is your aftermarket radio/chime adapter?

    (p.s.: https://forum.hptuners.com/forumdisp...-Tuning-Engine)

  3. #3
    Tuner in Training
    Join Date
    Feb 2024
    Posts
    15
    So I did do some reading about that. The truck came with an aftermarket radio. I had a draw problem a few months ago so all that got removed. I no longer have door chime. Dose the factory radio have to be on the bus system for some reason? I didn’t want to put in the I6 topics. seamed more like a bus problem?? Maybe common problem amongst chevy??
    Last edited by Fuse; 03-03-2024 at 10:40 AM.

  4. #4
    Did you resolve this issue?

  5. #5
    Senior Tuner
    Join Date
    Nov 2006
    Posts
    2,742
    about 4 times a year I have to repin customer DLC's cause they won't read. Maybe the pins are worn out at the DLC.

    06 Trailblazers are usually pretty solid about reading/ writing.
    Tuner at PCMofnc.com
    Email tuning!!!, Mail order, Dyno tuning, Performance Parts, Electric Fan Kits, 4l80e swap harnesses, 6l80 -> 4l80e conversion harnesses, Installs

  6. #6
    Tuner in Training
    Join Date
    Feb 2024
    Posts
    15
    No, I’ve just been using the bench tester. I may start pulling fuses for other control modules. On some other forms/Facebook groups this was the fix. Some even clam it was a tsb for the trailblazer but can’t seem to find that tsb. It’s a problem with too much chatter on the class 2 line I assume. It will read the pcm fine. Erase the pcm fine but won’t write.