99 Regal LS

I know everyone is tired of answering questions regarding PK2, but after hours upon hours of reading through the numerous threads on this site, I am convinced that my situation is somewhat unique so please give me a chance. I have a 1999 Buick Regal LS. The security light has been a permanent fixture on my dash for years. A few days ago the car wouldn't crank. All dash lights and accesories work as usual. One thing that seems to be unusual on my system is the two tiny white wires protruding from my key lock cylinder versus the seemingly more common three wire setup I have read about on countless sites and threads. After checking these wires I found that someone had cut them and then twisted them back together and wrapped them up in elec tape. Once I removed the tape it was obvious the had corroded apart. Just to check, I cut the ends, stripped the insul, and twisted them back together. As suspected, the car fired right up. Out of desperation, we drove the car the rest of the day and part of the next with no problems. Without thinking too much about it, I untwisted them and properly secured them with connectors, soldier, and shrick wrap. As soon as I was done, I turned the key and I haven't heard it crank since. I checked the resistance of the key side of the circuit at the connector under the dash and it would not register anything unless I wiggle the key. So I measured the resistance on the key itself which was a solid 7.5k Ohms. Soldered some resistors together to exactly 7.5k Ohms and attached one end of the sting to one white wire and the other side to the other white wire. Still won't crank BUT the security light is now off. I've tried the on-off relearn procedure a few times, no change. Another thing that concerns me is system voltage at the starter S terminal when in start postion, but I suspect the PCM controls current through resistance, not voltage. I have never had any typical starter problems before. I suspect a faulty BCM but I cant find any information as to diagnosing it and I hate to throw parts at it. This is the family wagon and our only car so any help would be great. Sorry for the long winded thread but I am absolutley desperate. thanks

Welcome to AF.

What is your "s" terminal voltage reading? Have you checked your battery and battery cables for corrosion or bad connections? Have you tried starting the car in neutral instead of park (this would indicate a worn PRNDL switch)

The voltage at the S terminal is battery voltage around 13V with the key turned to the start position. I have checked the battery and connections, all fuses and switched around relays. I checked the key cylinder circuit wires for resistance and continuity at the BCM and all is fine. Removed the resistors I installed and put the wires back together and the security light comes back on. There is no change in the lights when I turn the key, in park or nuetral, but it does show a small .5V drop in voltage at the battery when in the start position. I hooked up at push button start switch from the battery the the starter S terminal and it still wont crank. Seems extremly unlikely that the starter solenoid could be dead since it hasn't ever had any issues prior. Is there a way to check the output signal from the BCM? If so what would I check for and what pin? The Haynes manual only says it is a dark blue wire, but there are several dark blue wires at the BCM connector.

Then your issue sounds like a bad starter which obviously includes the starter solenoid or lack of starter B+ from the battery and not Passkey II VATS related even though you do have a security light issue. If the issue was Passkey II VATS then you would not have any battery voltage at the starter solenoid "S" terminal/purple wire.

:iagree:
It is probably just a coincidence if the starter/solenoid actually failed, but before replacement, be sure to have the battery load tested and verify that you have tight & clean connections. BTW, once you correct the problem with the starter/solenoid, if you want the security light out, reinstall the 7.5K resistor.

I just pulled the starter and had it tested. It did have a burnt motor smell, but the solenoid and motor engaged fine. According to the parts guy, it should at least click or make some attempt to turn. The flywheel turns with a prybar and all connections at the battery and starter are clean and tight. Reinstalled the resistors, security light out, still voltage at the starter S terminal, still no attempt to crank. I am totally lost....