"Car May Not Restart"

[DJRATEDR]

My step brother has a '99 Deville. He keeps getting a message that says, "theft system problem, car may not restart." After tearing apart the dash under the steering column I noticed that someone must've had a remote start and alarm installed. The VATS wires were cut and jumped together with resistors which I know must be done, as I'm a licensed mobile electronics installer, however, after futher troubleshooting and tampering ... I disconnected all the alarm wires and completely removed the system, reconnected the VATS wires and still got the message after starting the car.

At first I was thinking it may be the key or key tumbler/ignition switch, but then after more experimenting, I noticed the car would still start with the VATS wires completely disconnected. Am I to assume I'm right when I say the problem must be in the security module itself?

The purpose of the VATS system is to read the resistance from the key, right? If the car will still start with the wires disconnected, I'm assuming it can't be the key or ignition switch.

Since the car was not guaranteed to start regularly, I tapped into the constant hot and starter wire and mounted a push-buton alarm programming switch I had in my spare parts bin so that when the "starter disabled" message appears and car won't start he can turn the key to the on position, push the button and viola!

I kinda like it - LOL. It's like the new BMWs and Mercedes push-button start feature Might istall one in mine.

Anyway, does anyone have a clue what might be the problem?

Thanks for reading,

Reggie

[Cadillac Jim]

The first thing to do is to find out what the computers are really thinking. The way to do that is to read the OBD II device trouble codes (DTCs). On a Cadillac you don't need a code reader. See the link in my signature block on how to read the codes.

I get that on my car every few years. It's caused by a heavy keychain that swings when I drive, eventually wearing out the contacts to the resistor in the key. Eventually the contacts get a little flaky, and I get that message. I get a new key at the dealer (come in with the registration for the car, the old key, and the VIN number if you want a GM dealer to make you a key) and the problem goes away for another few years. The code I get is

B2780 (Wrong Resistor Before Good) HISTORY

From your narrative, it's probably a networking problem. Your codes will tell the story.

[Ranger]

An inline resistor is the method used to bypass the VATS system. The resistor matches the resistance in the key "pellet" (resistor). I suspect that is what someone did.