computer

1998 CHEVROLET TRUCK
280,000 MILES • V8 • 4WD • MANUAL
Avatar
DANNYBARTLETT
  • MEMBER
  • 1 POST
the truck is in theft mode, had a ground ,found it, now the truck starts and shuts off, had it to the dealer but they could not get into the computer to reprogram it plus it was 4:30 and they were leaving at 5 Now i got a computer out of a 97 the truck starts and runs but shes flooding and not workin right. the truck is manual shift does the computer have to be out of a manual shift truck? or do you know a way to get her out of theft mode?
Feb 15, 2009 at 3:05 PM
Advertisement
Avatar
KASEKENNY
  • CERTIFIED EXPERT
  • 18,907 POSTS
If the truck is in theft mode, then it is going to continue to start and shut off as this is typical operation in this mode.

Here is a guide that will help with getting it out of theft mode:

https://www.2carpros.com/articles/how-to-reset-a-security-system

However, if you had a dealer already try to get it out and they could not communicate with the ECM then this is going to be a greater issue.

At that point, either we have a wiring issue, or the module has failed.

What we need to do is check to make sure the DLC has proper power by checking the fuse.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

I attached the wiring diagram below which will help with this. If the fuse is okay, then we need to check the continuity from the DLC to the PCM (VCM on this vehicle).

Here is a guide that will help with this:

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Please run through this info and let us know what you find. Thanks
Image (Click to enlarge)
Attached Media
Nov 13, 2021 at 2:56 PM