00Corvette

My car is stuck in my driveway luckily. I went home the other day and it didn't fire right up, gave me nothing at all when I turned the key...showed a code that had to do with the key theft deterrent system, so I sprayed the key with electrical cleaner and wiped it off. Then wiped it with an eraser, went back outside and it started right up.

Just 45 mins ago I ran home again and went back out and she didn't start this time...

The codes are B 2721 PASS-KEY DETECTION CIRCUIT

AND

P 1631 THEFT DETERRENT START ENABLE SIGNAL NOT CORRECT


What do I have to fix now?

Thanks so much for any help,

Donnie

00Corvette

There's pretty much no way that the key pellet can break I guess, mine isn't loose and it's clean. So that eliminates that.

Should I start looking to the theft deterrent relay or the relay that is above the BCM?

Should I be looking at my lock cylinder or ignition system itself?

Please anyone, help me out here lol.

Donnie

Bill Dearborn

I would start by cleaning the contacts in the lock cylinder. From there it gets a little more involved. The P1631 code is generated when the BCM sends an incorrect password to to the PCM. The B2721 code issue has to be resolved before you can work on this one. Once you solve PassKey issue the other may just go away. If cleaning the contacts in the lock cylinder doesn't help then you may have a wiring problem in the resistance sensing circuit between the BCM and the cylinder, a bad BCM or a bad lock cylinder. Doubtful the theft relay is bad. It is just doing what the BCM is telling it to do.

Bill

00Corvette

Bill,

Thank you for the suggestions. How do I go about cleaning the inner lock cylinder? Should I pull it apart or just spray something up in there?

I'll start with that and disconnecting the battery, I get off work in about 30 minutes. So within an hour and half I'll be home and have the first two steps done lol.

Thanks again and I'll check back frequently.

Donnie

Bill Dearborn

I would spray something in the cylinder and then move the key in and out to help clean the contacts.

Bill

00Corvette

Bill,

Thanks so much for your help! I got it going again, just sprayed the cleaner in the cylinder like you said and wiggled the key around.

Fired up no problem, codes went away and security light turned off.

I might eventually have to get the new cylinder but for now, thank you som much once again!

Donnie

bighank

If you read my post H E L P ! ! ! Turn key in ignition NOTHING you will see I had these codes and a few others but essentually the car would not start. Do you think you have solved the problem or are you keeping your auto insurance towing number in your hip pocket like me? BIGHANK

bighank

I spreyed contact cleaned in the ignition switch and worked the keys in and out. Car restarted several times without any codes. Not sure that I have fixed the problem. BIGHANK

Chris Murphy

Does anyone know what the difference is between the three different codes that have the same description?

b2721 b2722 b2723?