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Gary, GMC Technician
Category: GM
Satisfied Customers: 17030
Experience:  15 years gm master tech/15 years ASE master tech
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We are installing a 1999 engine in a 1995 pickup. we have

Customer Question

We are installing a 1999 engine in a 1995 pickup. we have changed vcm that came with the 1999. do you have any idea how we can get around the security to make it run.Right now it will start then die.
Submitted: 2 years ago.
Category: GM
Expert:  Gary replied 2 years ago.

I am sorry your having this problem

since there is NO BCM in this truck the VCM is looking for a coded signal from the BCM for the theft lock or unlock and since there is NO BCM the VCM will always go into theft / security lock

the only way to get around the security system lock that you are running into is to have the programming for the security system removed from the VCM

this can be done by either sending the VCM to a customer programmer like this company :

OR do a search and see if there are any local auto computer programmers / tuners local to you as some will come to you and plug into the trucks computer and program it to shut it off or remove the security programming from the VCM

the dealer just has the stock programming for this VCM so they can not help you

that is the only way to stop the security in the VCM for shutting off the truck i am sorry to say