Okay so I have a 2003 VUE 3.0 AWD and I replaced the BCM with a good one from a u-pull yard. I decided I’d put in a Bulldog remote start/lock system I had new in the box. I got everything wired in but the car does 5 seconds after starting. I have already bypassed my pass lock system with the inline resistor. But the car with the key light stays on till it shuts down. I don’t want to by a bypass module when I’ve already bypassed the system. Is there somewhere I need a ground signal to go or something so the car thinks the key is there? I tried grounding the return line from the pass key to the Bulldog module (It has a wire that grounds while the remote start is running) but that didn’t work. Any other ideas? Thanks

 

If the passlock II security light stays on and the engine stalls in 5 seconds, either you have not correctly bypassed passlock II or the Passlock II reset procedure needs to be run to marry the " new BCM" to the PCM. I suspect the latter as you did not mention doing the Passlock II Relearn after BCM swap.

The procedure is all over this and other Saturn/GM forums. Google "passlock II Relearn" and you'll find it.

Follow it to the letter or it will not work. Perform the 30 min version and have the battery attached jumper cable style to a running vehicle as the key will be in the run position most of the 30 min and it will drain your battery, forcing you to begin anew.

If the relearn dies not work, the replacement BCM may be faulty or incompatible

 

I did the BCM relearn when I did the bypass and when using the key it works flawlessly. The security light only comes on during a remote start.

 

If you send me links to the wiring diagrams for both the passlock II and remote start system I will try to sort it out.

My swag is that when the remote start wiring is connected, it changes the effective resistance that the BCM sees coming from the ignition switch. It therefore no longer matches the expected resistance and therefore triggers passlock.

Back in the olden days, when everything was constructed from discrete components, something like this would probably be the equivalent of closing a relay that had a zero resistance or close to it once closed. Now that everything is on a chip, you have pull-up resistors for transistors such that they conduct the right amount of current at the right voltage under the conditions you want blah blah blah blah blah

Most transistors, when turned on, have a nonzero resistance on the current path. I'm thinking that may be what is affecting the resistance seen by the BCM if it is wired in series or in parallel with that bypass resistor.

Then again I have never touched one of these systems. I'm game if you are.