exracer28

Has anyone reprogrammed a BCM? On my race car I want to delete some of the DTC checks and delete the FOB requirement

C6Roadracer

Can you even do that. I am not aware of any of the reprogramming software that can do the BCM.

'VETTE PHASE

If you know someone with a Tech II, that would be your best bet.

exracer28

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.

'VETTE PHASE

What if you could mimic the "OK" signal that the RCDLR sends to the BCM? Connector 1 pinout L on the RCDLR is the RFA Class 2 Serial Data. Monitor the 1045 circuit with your Tech II to see what type of signal is sent when you start the car with a known fob. If it is a voltage or a resistance, maybe you could intercept the wire from the RCDLR to the BCM and, using a toggle switch, mimic the "OK" signal. You would have to get in, flip the "OK" switch, and start the car normally.

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.

tjwong

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.