I have a 96 z28 and I just had my computer tuned from pcmforless. They sent me a different computer with the tunes I needed(one of which was to turn vats off). I unhooked my battery, removed the old pcm, and inserted the new one. Plugged the battery back in and started my car it started right up nothing wrong....I turned the car off and attempted to turn it back on and the security light turned on and nothing happened the car wouldnt start it made a noise maybe the fuel pump turning on but i dont know. Definatly no starter. What happened? My first guess is that the electronic sensor thing(not sure of proper name) inside the key stopped my car from turning on since it is a whole new pcm. But why did it start the first time? I figured getting vats programmed out would bypass the key sensor.

 

Quote: I figured getting vats programmed out would bypass the key sensor.

it does

 

The VATS ' Theft Deterrent Module " (TDM) does a few things, 1- it feeds a 50hz signal to the PCM that tells it to pick the injectors, this prevents starting and is what is programmed on or off in the PCM. However the TDM also picks the "Theft Deterrent relay" TDR that allows the starter solenoid to pick (prevents cranking), this is NOT programmable and requires the key bypass modification or bypassing the TDR. The TDM also controls the security lite sequenses, off after 5 sec = OK, solid on block subsequent starts for 5 mins, blinking = TDM failure, etc. http://shbox.com/1/pass_key.jpg

 

Ok. So do I just put a jumper across A1 to C2 and A2 to C1 or do I take out the TDR and add the jumpers? Or am I completely missing something. Im not a genius when it comes to one line diagrams.