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tccm

  1. 2002 Envoy, from CV axels and TCCM

    4x4 Drivetrain
    Hi!! I just got a second hand Envoy from 2002. The moment I bought it I took it to the mechanic and they told me that the front CV axels are bad and that I have to change them. When I bought it I also knew that the TCCM module has to be changed because the 4WD service was on, and the mechanic...
  2. 4X4 doesn't work, I've tried everything!!!!

    4x4 Drivetrain
    Hi, I have a 2003 Trailblazer LS. 4.2 I6. 112k miles. I have the service 4wd light on, the check engine soon light on, ABS and brake and air bag lights also on. No cruise control working, and no 4x4, no lights on the selector switch except at start up when it performs a bulb check. I have...
  3. [SOLVED] NOT SOLVED!! Reset transfer case control mod, now engine wont start...

    The 02-09 "How-To" and DIY Section
    As the title would imply, I did a reset on my TCCM because I cant get my 04 envoy to come out of 2 wheel drive after having replaced the transmission. I did this by unhooking the battery, and unplugging the TCCM (hooking back up in reverse order) as a mechanic friend told me to do. However when...
  4. No Start, odd behavior

    General
    Hey everyone I have been on this forum ever since I purchased my 03 LS 4WD and pretty much every little issue that has come up I've been able to find an answer for. So, I thank everyone on here for that. Now, I have a real head scratcher, my truck won't start at all. No work done recently...
  5. Trans slipping out of overdrive & 4WD stuck: 1 issue or 2? Help.

    4x4 Drivetrain
    This is a bit convoluted, so I'm going to try to explain this mess with bullet points: * First issue was car would not switch back into 2WD from 4WD high. If I turned switch, all the lights would flash quite a few times, then it would go back to 4WD high and stay there. Car was...
  6. 4wd indicator light isn't working

    4x4 Drivetrain
    A while ago the lights on my 4wd went off and would not come on no matter what selection I was in. I'm getting no service 4wd light on the dash, no clunk whenever I switch to 2 or 4wd, nothing. I've already read up a little and pulled and check fuse #8 and also disconnected and...
  7. Have tried almost all 4X4 fixes...now i have no forward or reverse

    4x4 Drivetrain
    My 4WD has worked flawlessly on my 02 Trailblazer LTZ (133,000 miles) up until a week ago. During a snowstorm that dropped 30" on Northern MN I had a complete failure of all systems. I selected 4WD LO while at a stop and I heard a clunk. After that I had no forward or reverse. I have been...
  8. Need help diagnosing transfer case issue

    4x4 Drivetrain
    Hello, all. This my first post to the Trailvoy Forums. I searched through other threads that seemed related, but I couldn't find the info that I think that I need. I have a 2002 Envoy SLE that I just purchased used. It has 234,000 km on it (about 144,000 miles). When I purchased it, it had...
  9. 4WD doesn't work, #48 Under seat keeps blowing

    4x4 Drivetrain
    Hi all, I am a first time poster, but need some help. I have scoured the threads and have not found my exact issue. Since I bought the vehicle the 4WD selector switch has been dark and I have never had an indicator light on the dash. I tried pulling #8 under the hood, but it did not help. I...
  10. Help with 4WD issue

    4x4 Drivetrain
    So my 4WD seems to be stuck in A4WD. I have searched through the forum and found a lot of good information but I think I still need some help diagnosing the problem. The service 4WD light is on. And the selector light is stuck in the A4WD position. I took it to a local transmission shop for a...
  11. Rough Idle / How do I Check a coil? / TCCM

    OEM Issues
    Hello everyone, and thanks in advance! '02' Envoy SLT 4.2L I-6 90,000 (bought it from my sister 2 yrs ago it's been babied) And I Love it! I've had some common problems. Battery went dead shortly after I got it. It set the "service 4WD" light Installed new Battery, tried all the tricks had to go...
  12. 4x4 switch/TCCM

    General
    I have been reading other posts about probs with the switch on the dash and/or the TCCM, but what led to repairing/replacing either of those isn't similar to the issue i have. About 2 weeks ago, i turned my truck on and the light on the switch showed it was in 4hi, but the switch was pointing...
  13. 2002 Trailblazer Encoder Motor/TCCM problem

    4x4 Drivetrain
    Hi Everyone, Here is my story- I have Trailblazer 2002. Initially I swithed the nob from 2WD to Full 4WD, the light kept blinking but didn't feel any engaging, and once in a while this also triggered Service 4WD light on. Brought the car to dealer and it was told Encoder Motor problem and...
  14. Encoder Motor/TCCM or anything else

    Introductions
    Hi Everyone, Here is my story- I have Trailblazer 2002. Initially I swithed the nob from 2WD to Full 4WD, the light kept blinking but didn't feel any engaging, and once in a while this also triggered Service 4WD light on. Brought the car to dealer and it was told Encoder Motor problem and...
  15. How to change TCCM - transfer case control module

    4x4 Drivetrain
    Hey, I'm sure there's info on here, but I'm terrible at searching through threads. Just wondering if anyone knows a link or has detailed info on how to change the transfer case control module on an Envoy. My service 4wd light came on, and no lights show up on my switch anymore, so I'm assuming...
  16. A4WD Bumpity-Bump (feels like driving over expansion joints)

    4x4 Drivetrain
    Although I thought I'd be able to add this to an existing thread, but none appear to be quite the same - I'd be hijacking someone else's thread instead of adding useful info - so here goes with a new thread. Hopefully this will be useful to someone else down the road. 2004 GMC Envoy XUV with...
  17. EBCM vs TCCM - Who's right?

    4x4 Drivetrain
    So my 04 TB has the dreaded Service 4WD light on and no lights on the selector switch. After browsing the forums, I tried 1) removing #8 fuse, no luck. 2) went to the dealership for their diagnosis. They tell me its the EBCM and with labor going to cost $700 to replace. 3) As I generally...
  18. No 4X4.........At All

    4x4 Drivetrain
    Hello all! Just a newbie here looking for some answers. I read all of the threads pertaining to this and I haven't seen anything that has exactly what I need. I have an 02 TB and it will not shift into anything other than 2wd. The indicator lights above the positions on the dial switch do...
  19. Tccm/pcm/bcm work independant of each other?4wd swap

    Transmission Mods
    Tccm/pcm/bcm work independant of each other?....... Curious if the Bravada/Trailblazer pcm/ tccm /tcm work independently of one another......Studies indicate yes!!! Does the pcm really care which tcccm/t-case is used?.... If so is it something that can be re-calibrated/reflashed.... My...
  20. Parasitic Battery Drain

    02-09 Vortec 4.2L I-6 Engine and Drivetrain
    I have an 02 Trailblazer with a battery drain problem. I have isolated the problem to the TCCM or something connected to it. When the TCCM is unplugged the problem goes away. Has anyone else had this problem, and if so how did you fix it.
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