2002 Z06 with 40k miles. Yesterday, I ran over to a nearby convenience store and when I left, I noticed the SECURITY light stayed on. The car ran fine and the problem did not reoccur when I turned it off and restarted. Not sure if that's related or not but I thought I'd mention it just in case it is.

This morning, the car wouldn't start. When I turned the ignition on, the dashboard lights went through their normal sequence and everything appeared normal, but when I turned the key the starter didn't even try to turn over. Absolutely nothing. My first thought was a security issue. My '95 will sometimes misread the resistance of the key and you have to wait a few minutes, reinsert the key and try again. So I waited, then tried again. This time, the car started but immediately died. I tried it a few more times and it did the same thing. It would start but then immediately die. Pressing the gas pedal had no effect.

I got out of the car and waited a bit, trying to figure out how I was going to get to work, then figured I'd try it one more time. This time, it started normally. I drove it to work and now I'm sitting here hoping that it'll start when it's time to leave.

I know this isn't a lot to go on but if anyone has any ideas, I'd be happy to hear them.

 

Codes are:

10 PCM P1631H

28 TCS C1276H

40 BCM B2721H and B2723H

PCM and BCM codes seem to indicate a security system issue, which fits what I first thought. Does the security system kill the fuel pump? If so, that would explain why it was starting and immediately dying.

Not sure about the TCS code, although I'd suspect that that is unrelated to this issue.

 

Both BCM codes deal with the pass key. You may either have a bad/dirty key or ignition switch.

 

The only other code was a radio code, because I have an after market unit in the car.

I have another key and can clean the switch if that's the issue. What concerns me is the fact that the security light stayed on when I started the car the day before and the 10 PCM P1631H code, which is "Theft Deterrent System Password Incorrect." I'm not sure what password they're talking about. If that's the resistive value of the key, then it's probably just a dirty key/switch or similar. But if that's some sort of code stored in the car, it may indicate a more serious issue with the security system.

 

I've been having the same problems, there's alot of good info here. NEVER would have thought it may be key related

Gotta love the forum

 

8VETTE7, thanks for the solid info. I'm still puzzled by the security light staying on the day before but I've started the car a dozen times or so since the incident using the same key and have had absolutely no problems. For now, I'm assuming it was a one time glitch (something as simple as a bit of pocket fuzz getting caught on the key can occasionally cause this) and move on. Thanks again.

 

When the car would not turn over, was the security light flashing at the time? If so, it was the pellet contacts in the switch and the flashing would disable the TDR relay

 

i am experiencing a similar problem now too. over the last few months, i have sporadically had times when my 2001 c5 a4 55k miles fails to start. this was never a recurring situation, so i just tried to keep my only key as clean as possible. however...

i recently paid for a detail job and upon my next start up noticed the security light stayed on, even while driving. this has never been part of my experiences through the failed start up process. today, i went to run an errand and am now experiencing both issues simultaneously - the car wont start nor is the security light turning off (not flashing but stays on). i've checked the codes and the only current issue is 40BCM - B2723 H C. i understand that this relates to the PASS - key detection circuit. but, i am very cloudy on what i should do from here? new key? ignition switch? please help as this is my daily driver. thanks!