Hello I'm a first time poster. I race dirt track 4 cylinder and sometimes v8s. I lost my key to my future race car.So I did what I nomally do and broke the ign.switch out of the column.Oops. Well come to find out the key turns a magnet past a sensor that tells the body module that everything is o.k. Now the pcm only gives a momentary pulse to the injectors and the engine dies. What I want to Know is, what goes through the data wire(pink) going to the pcm from the body module?Is it a ohms reading or what? The simpler I get the wiring, the less trouble it is to fix a problem when one occurs. THANKS #7

you already asked and got a response



My car may run 18s, but I can do your taxes in 10 seconds flat.
JBO lube - they would never have enough in stock and we'd never see RodimusPrime again

I sorry, did you tell me how to do this?Thanks

the magnet waiving by the sensor gives it a momentary voltage pulse. you would need to duplicate that. or, since it is a race car, you can just figure out what the ecu needs to think that the bcm said it's ok and duplicate that. Also, i think there is a product out there to bypass the bcm for when you install alarms and such

Brian Balcom wrote:Hello I'm a first time poster. I race dirt track 4 cylinder and sometimes v8s. I lost my key to my future race car.So I did what I nomally do and broke the ign.switch out of the column.Oops. Well come to find out the key turns a magnet past a sensor that tells the body module that everything is o.k. Now the pcm only gives a momentary pulse to the injectors and the engine dies. What I want to Know is, what goes through the data wire(pink) going to the pcm from the body module?Is it a ohms reading or what? The simpler I get the wiring, the less trouble it is to fix a problem when one occurs. THANKS #7

The gist of what you need to do in order to bypass GM's Passlock I interface, is to replicate the resistance value that is delivered by the ignition when the key is in the cylinder.

There are 3 ways to do this that I know of (and if I understand correctly, you are not able to turn the tumbler with the key right now, so my words of wisdom are, "good luck" and "have fun":

1) Use a resistor of the same value and relays CLICK HERE FOR A DIAGRAM (the diagram is located at the very bottom of the page)

2) Jumper the Passlock wire to the ignition switch CLICK HERE FOR A WRITE UP

3) Install a Passlock I PLJX or PLXR bypass kit
CLICK HERE For Information On The PLJX
CLICK HERE For Information On The PLXR

Your best bet might be the PLXR (which has been replaced by the PLJX, so it might be a little harder to find, but there are still tons out there). With the PLXR, though it will be a pain in the arse, you can select the resistance value that it outputs by using the built in potentiometer. In your case, if you can not get a value by using the key, you will have to sit there and turn the potentiometer dial in small increments and test it after each turn. This will take a long time, but, you may luck out and find the correct value on your first couple of tries.