What are TCM PCM ECM VCM upgrades?

[56Nomad]

I am planning to take my 2002 Chevy 3500 in for
re-flashing of the Allison and the Dmax engine for
any applicable upgrades. I have 16000 miles on the truck.

From reading past posts, it is recommended to have the
dealer do TCM PCM ECM and VCM upgrades.

My question is what do these acronyms mean?

Thanks

[ 10-13-2002: Message edited by: 56Nomad ]</p>

[SoMnDMAX]

TCM- Transmission Control Module
PCM- Powertrain Control Module
ECM- Engine Control Module (or) Electronic Control Module
VCM- Vehicle Control Module, also referred to as the BCM- Body Control Module

[mdrag]

56Nomad,

Looking through the 2001 Helm's manual when I was trying to locate the ECM for the high idle install last year - I noticed the manual refers to the PCM on the gassers and ECM for the Dmax. It seems most use PCM and ECM to mean the same thing.

[SoMnDMAX]

Mdrag, as far as I know, the 6 liter and smaller gas powered trucks (and cars) use a PCM which controls both transmission function as well as engine functions. The Dmax uses an ECM which controls engine function exclusively.

[Kennedy]

It should be listed on their TIS program as ECM/PCM, and TCM/VCM IIRC.

Either way they are TWO seperate programs/downloads, and will require 2 trips in and out.

I had a customer in last Tuesday with a 2002 CA truck. We took it in for these updates, AND did the Allison fast learn. Total time was approximately 1/2 hr. Customer is now enroute back to CA towing his 5th wheel STOCK, with only gauges to establish his baseline.

[56Nomad]

Hi John,

I am a little confused.... still. For me, not hard to do :D

In a previous post on this subject you had written:
"What you want to do is have the dealer hook up the Tech 2 to the vehicle. Select Service Programming/Request inf.

It will show your vin and current calibration levels. Never hurts to write these things down and keep with any other useless inf you have...

The Tech2 is then hooked up to the GM computer where you select: Tech 2, Reprogram ECU, In vehicle. The following screens are simple, click next, verify vin, the next screen should show: PCM/VCM on one line and TCM on the other. Select PCM/VCM download, and off to the vehicle you go!

Back into service programming, select Program ECU, it reprograms and tells you when done.

THEN do it ALL over again! Only difference is, this time you select TCM!"

Thanks for all your help.

Howie

[Kennedy]

Simple outline:

1) Hook Tech 2 to vehicle, and extract VIN/calibration information.

2) Hook Tech 2 to SVC PC and select module to reprogram.

3) Select appropriate calibration pkg (usually Fed vs CA emmissons etc and download to T2

4) Connect T2 to vehicle and reprogram.

5) Repeat for the other module to be programmed.

This is from memory as I have operated the GM system, but not my own. I guess I gotta purchase a laptop so I can get mine going...