Reprogram BCM
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,576
Likes: 85
From: Sumter SC
I have a tech II and it reads or loads GM software. I am not aware of a process to rewrite the software with a tech II. It appears that the program reads the serial data between the BCM and Keyles entry reciever to determine if a matching FOB is present. It might be too simple thinking but if the software was changed to make the answer always true then the stock start button could be used to turn the car on/off.
Melting Slicks
Joined: Aug 2006
Posts: 2,167
Likes: 11
From: Powell TN
Cruise-In VIII Veteran
I have a tech II and it reads or loads GM software. I am not aware of a process to rewrite the software with a tech II. It appears that the program reads the serial data between the BCM and Keyles entry reciever to determine if a matching FOB is present. It might be too simple thinking but if the software was changed to make the answer always true then the stock start button could be used to turn the car on/off.
You would still have the problem of opening the door without a fob since the RCDLR sends a ground to the latch when it recognizes a fob and then tells the BCM that everything is "OK". The BCM then sends 12v+ to the latch, opening the door. The latch is just a small electric motor. The door handle is just a contact patch, so you may be able to run 12v+ straight to the motor and then run a ground through the door handle back to the motor. Squeeze the handle, sends a ground, motor runs, door opens.
Last edited by 'VETTE PHASE; Jan 22, 2009 at 12:05 AM.
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
It isn't possible to reprogam the BCM using a T2 to do what you want. If this is a race care, rip the BCM and the RCDLR module out of the car, and hot wire the door latch mechanisms as mentioned above, and delete the VATS from the PCM, then wire in a IGN switch and a START button to crank her over to start it up. That is exactly what we did for a customer some time ago. Window controls and such take a lot more work if you actually remove the BCM, but its doable if this is a RACE car and not a driver on the street.
