40bms B2723 Won't Start

[TODD L GRIFFITH]

40BMS B2723 Won't Start

I got this code after taking my Z out for a test drive on new fuel injectors. It is a passkey detection circuit code out of the body control module. I was doing some tuning and set the alarm off either accidently, or it was triggered. I'm not sure because the key fob was in my pocket and I may have activated the panic button, not too sure. I couldn't shut the alarm down right away, so it drained my battery some. I recharged the battery and the code remains 40BCM B2723, with a no start condition. I went through the dic and with my scanner and cannot erase the code. (*****!) The check engine light is on and the security light is steady with the key in the on position. I do not have another key with the resistor, but took the key to the dealer where they have a lock cylinder simulator and the resistor is good, and shows the key code. When I try to start the car all accesories light up, and the fuel pump runs, with the key in the on position. When I turn the key the rest of the way for start, everything seems to die, no starter or even a starter click. I'm also in the stupid column lock, and it will not back off, but no column lock code is present. I have an appointment with the dealer Monday. It most likely is a worn or broken ignition cylinder circuit for passkey. If anyone knows anything else, or have been through this before, please let me know. Maybe save me a trip to the dealer and a tow. I know these map glass batteries have to have a good charge. It may seemed charged fully, but I know that this VATS system is a finicky bastard. Any ideas, glad to hear them. I tried a passkey relearn just in case, but with the code present it is useless.

 

[c4c5specialist]

Hi there,
This code is not only for a password that is invalid. You could have an open circuit in the system, or a short to ground.
The Interrogator is what we use to generate a signal without the use of the key. This will tell us if all the wiring going to and from the BCM is good. Also, if the lock cylinder is bad, the tool will also tell us that.
You could have a chaffed wire, or the contacts could be worn enough that you do not have correct continuity inside the lock cylinder.
Allthebest, c4c5

 

[TODD L GRIFFITH]

Thanks c4c5, I was hoping you would see my post.

 

[TODD L GRIFFITH]

Update c4c5. Never took the car to the dealer. (not yet) I checked the resistance of my key (7500 ohm) I put the key in the ignition cylinder and checked the circuit's resistance, nothing, had an intermittent open on the purple/white and white/black resistor pellet circuit to the BCM. I installed a 7500 ohm variable resistor in the circuit and she fired right up, column unlocked. I will go to the dealer later for the new ignition cylinder. Right now I'm concentrating on my PCM learning the new cam tune which is going great, with time and miles.

Thanks Todd