tach problems on a 2000 Cheverolet truck

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=26744
Printed Date: July 16, 2025 at 2:46 AM

Topic: tach problems on a 2000 Cheverolet truck

Posted By: gcar80
Subject: tach problems on a 2000 Cheverolet truck
Date Posted: February 18, 2004 at 6:19 PM

Where do I find a tach source for a remote start alarm. The truck has individual coils for each spark plug and I cant find the white wire to tap onto. Can I find this wire under the dash. I have looked at this sites vehicle information and it says a white wire at the coil but I can't seem to find it. Could it be possibly be at the ECM?

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magyver

Replies:

Posted By: sparkie
Date Posted: February 18, 2004 at 6:41 PM

The white tach wire you are looking for is found at the gauges/instrument cluster. Pull the trim panel surrounding the cluster, radio and climate controls rearward. The panel is clipped in place. Remove the four screws surrounding the gauges. The plug going into the gauge cluster has one white wire in it. This is the tach signal from the engine's PCM. You could also use the odd colored wire at any of the coils for a 1 cylinder tach signal. The coils have four wires going to them. Three wires are the same color at every coil and one is different at each coil. The odd one is the tach signal for that cylinder.

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sparky

Posted By: gcar80
Date Posted: February 18, 2004 at 6:46 PM

I kinda figured that the odd wire to the coils was the tach source but I knew that there had to be some other way thanx

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magyver

Posted By: gcar80
Date Posted: February 18, 2004 at 6:46 PM

I kinda figured that the odd wire to the coils was the tach source but I knew that there had to be some other way thanx.

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magyver

Posted By: gcar80
Date Posted: February 18, 2004 at 6:51 PM

I kinda figured that the odd wire to the coils was the tach source but I knew that there had to be some other way thanx. The alarm that I have is the Audiovox Prestige Platinum Remote Start/ Full Alarm System. It has a 4 pin plug thats called the Auxiliary outputs. All it reads is pulses before and after start, after shutdown, and during crank. The book doesn't say what it goes to but Im assuming that its for flashing the parking lights at those times of remote start

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magyver

Posted By: gcar80
Date Posted: February 18, 2004 at 6:53 PM

Also the alarm only has one door trigger wire input and at the BCM I found an individual wire for each door pin

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magyver

Posted By: kgerry
Date Posted: February 19, 2004 at 1:03 PM

either go to the dome light for a single trigger or diode isolate the wires at the BCM and use them all

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Kevin Gerry
Certified Electronics Technician
MECP First Class Installer

Owner/Installer
Classic Car Audio
since 1979