2004 Chevrolet Express CargoVan tach wire
Printed From: the12volt.com
Forum Name: Vehicle Wiring Information & File Requests
Forum Discription: Request Car Alarm, Car Stereo, Cruise Control, Remote Starter, Navigation, Mobile Video, and Other Vehicle Specific Wiring Info, Manuals, Tech Tips
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=74335
Printed Date: July 13, 2025 at 11:50 AM
Topic: 2004 Chevrolet Express CargoVan tach wire
Posted By: nima
Subject: 2004 Chevrolet Express CargoVan tach wire
Date Posted: March 12, 2006 at 6:51 AM
I want to know where the other place that i can get TACH wire b/c PCM is hard to reach on this VAN.
Replies:
Posted By: xscash
Date Posted: March 12, 2006 at 8:04 AM
try the odd color wire on any injector
Posted By: nima
Date Posted: March 12, 2006 at 8:20 AM
where is the injecter. i took the PCM and by diagram i connect the pin 26 wich is perple/white but does not work.i try all perple wire @ PCM did not work is there any other color on PCM
Posted By: xscash
Date Posted: March 12, 2006 at 8:23 AM
fuel injector...on top of motor
Posted By: xscash
Date Posted: March 12, 2006 at 8:25 AM
i also have white wire at the pcm
Posted By: nima
Date Posted: March 12, 2006 at 8:27 AM
Is it hard to reach the injector I try the white wire on PCM but did not work my van is 6.0L engine
Posted By: nima
Date Posted: March 12, 2006 at 8:36 AM
How can i tell if i have PASSLOCK II system in my van.my van is cargo van it does not have power lock or power windows. it is basic van
Posted By: Velocity Motors
Date Posted: March 12, 2006 at 9:41 AM
The tach wire on the Express van is a BROWN / WHITE wire found at the PCM. BROWN / WHITE (between two yellow wires) Pin 73 in C1 (blue plug) of PCM ( this is the first plug on the engine side of the PCM. It's not actually a BLUE colored plug on the outside, but does have the word BLUE embossed on the PCM casing ). The PCM is located on driver's inner fender. There are several BROWN / WHITE wires, you will need to test for the correct one.
All the Express Vans that I have worked on have the Passlock system in it. If you have the yellow pad lock on the top left side of the gauge cluster, then you have Passlock on this van. I just worked on a G-Van 3500 cube style yesterday.
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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA
Posted By: sparkie
Date Posted: March 12, 2006 at 10:35 AM
A very easy to reach tach source is am ORANGE / black wire for an injector. The wire can be found at the top corner of one plugs in the PCM. It is in the plug closest to the motor. You don't have to remove the plug or PCM. It is visible at the top corner of the PCM and can be spliced into easily. It protrudes out of the open side of the PCM plug. I have stopped using the white wire in the green connector of the PCM since I found this source. It saves a lot of time and effort. All GM trucks/vans built from 1998 and on have Passlock II, except those built with a police package.
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sparky
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