TCM Location

[SimplyRAD]

Hello GM-Tech,

 

I was wondering where the TCM is located.

 

I am still getting a P0700 code and the dealerships around here want to charge me again to run another diagnostic. I was thinking of just replacing the TCM and start from there.

 

BTW: It is a 2001 8.1 4x4 w/Allison DRW.

 

TIA

[GM-Tech]

It's on the radiator shroud, driver's side. On second thought, that's the diesel's location, but I suspect the 8.1 might be the same. Don't see many 8.1's around here.

 

But I think you're wasting your money to replace the TCM. A P0700 in the PCM just says the the TCM requested the PCM turn on the Engine light. The real DTC is in the TCM.

[redvett]

Hello GM-Tech,

 

I was wondering where the TCM is located.

 

I am still getting a P0700 code and the dealerships around here want to charge me again to run another diagnostic. I was thinking of just replacing the TCM and start from there.

 

BTW: It is a 2001 8.1 4x4 w/Allison DRW.

 

TIA

 

<{POST_SNAPBACK}>

 

 

 

Changing the TCM wont solve the problem. You need to have someone diagnose the problem not change parts. Why heck you could change everything related before you find the problem. Take it to a dealer you respect and have them fix it.

[SimplyRAD]

It's on the radiator shroud, driver's side.  On second thought, that's the diesel's location, but I suspect the 8.1 might be the same.  Don't see many 8.1's around here.

 

But I think you're wasting your money to replace the TCM.  A P0700 in the PCM just says the the TCM requested the PCM turn on the Engine light.  The real DTC is in the TCM.

 

<{POST_SNAPBACK}>

 

 

 

Update:

 

I took my truck to a mechanic I trust and he had found that the connections to the TCM and the Ignition switch were faulty as in, "loose and some of the connections were getting hot(blue color)". He had also firmed up a ground wire.

 

Thanks, you two saved me six-hundred somethin' dollars. I am now getting the headers installed with a true 3" dual magnaflow setup.