Q: My car won't start 0 1996 Buick Park Avenue

Before you go digging for the starter motor theft deterrent relay, I suggest making sure it is indeed a problem. Check for power at the purple starter solenoid wire while the key is in the crank position. If you have power there, the relay is working, if not, it could be the relay or the anti-theft module is not grounding the relay. These modules don’t fail to often, so if it isn’t grounding the relay, there is probably a passkey problem.

Passkey systems have one very common failure. The two wires that are connected to the ignition lock cylinder break. This activates the security system. This circuit can be tested by accessing it down below the drivers shins, following the combination switch wiring harness. There is a small white/black wire and a small purple/white wire. Use a multimeter to see if there is continuity in this circuit. If there is, the circuit is most likely good, but the next challenge is whether or not it is the correct resistance value.

The resistance value is determined by the pellet embedded in the key. If you made a new key without the pellet, your security system will not enable. If there is a change in resistance in this circuit, the passkey system will not enable the theft deterrent relay.

If you must go after the relay, my information system states the relay is, "behind the left side of dash, left of steering column". Unfortunately, this is common in the industry not to have very clear instructions. The next thing to look for while looking for this relay is the wire colors. There are four wires. two yellow wires and two purple wires. And in true automotive confusion, I have accessed this information in two parts of the Mitchell system. The wiring diagram says the relay is, "right of the instrument panel".

As I said before, this is par for the course unless you can get access to a factory repair manual. What usually happens in a case like this is you have to dig for the relay with the color combination stated above. Once you find the relay, you have to supply power to the correct wire. I am not going to state which one since adding power to the wrong wire can damage a module. If you are inclined to do this, you will need to find a wiring diagram and apply power at your own risk. Another option is to check for continuity from the relay connector to the starter motor. If you have continuity, you have found the correct wire.

If you find this is to daunting to make sense of, I recommend booking a car is not starting inspection.

Good luck! I hope I have helped you out.