My Dad has a 2002 Bonneville SSE. He recently changed the battery under the seat (its vented too), but did not use a memory saver. He switched the batteries and then the car would start intermittently, but would then shutoff. Now, when you turn the key, you just here a click and the engine won't turn over.

The guys at AutoZone said that he erased the PCM and have to take it to a dealer to get it reprogrammed. I didn't know if it was that or an error in PassLock III.

If this is the PCM, can it be reprogrammed without a dealer? Replacement PCM?

Any other thoughts?

Thanks

I did search the forum for answer. Maybe I missed it.

If your just hearing a click I suspect your not getting enough voltage to the starter. Check all the batter cables for corrosion. Check for voltage at the starter. Is the security light flashing or on steady?

He didn't erase the PCM. I had my battery disconnected for over 24 hours and it started back up just fine. If the security/Pass-3 was the issue it wouldn't click at all. You would turn the key and the "SECURITY" would stay on on the dash.

The starter either isn't getting enough amps or is stuck for some reason

When you brick a PCM it will not enagage the starter, I did it trying to write a PCM, try jumping it and checking the cables

Thanks for the replies, so far.

security flashes when the key is turned to the "Accessories" mode

When the key is turned to ignition, everything turns on like normal. The "Security" indicator will come on at this point, stay solid for 2-3 secs and then turn off.

We'll try to jump it and check the cables.

Again, thanks.

Everything sounds normal. If a connection is corroded the lights will work fine. But will dim when you try to start.

OK, got it figured out. What everyone said was dead on.

The problem was a loose nut on a bolt that holds the battery positive cable lead and the starter cable lead together. We checked the voltage there first and it was 12V - wouldn't start. (Scratch head) We then were able to jump it and it started. (Scratched head some more). While we were watching it run, I noted some smoke coming from this bolt holding the leads together. We wiggled the cable and the car died. With the engine dead, we wiggled the cables more and the lights would dim. (I assume the smoke was coming from the bolt that was heating up and melting the plastic around it.) Turn the key, and it started again.

There was a lot of wiggle room between the two leads. So, much that a bump in the road could stop the connection making the car shut down while driving. We were not able to tighten the nut down anymore, so we put 2-3 washers between the nut and the leads. With everything tightened down, no more play and no more care car shutting down and this time it would start too. We test drove it around for 3-5 miles go over bumpy roads too, and it never missed a lick.

Thanks y'all for your help. You saved my Dad some money.

Any time. We know our cars.