Tried starting 98 C5 yesterday, battery was completely dead. Charged overnight and had 12.84 measured at battery terminals. Reset key fobs and they locked, unlocked and opened the trunk. Lights, horn, radio and heater blower motor all work. The key [FONT=inherit !important][FONT=inherit !important]slot[/FONT][/FONT] is NOT vertical when ignition is off and key is out of ignition but is almost on the dot on the plastic to the ACC position. Tried starting car. All gauges go to zero and [FONT=inherit !important][FONT=inherit !important]accessories[/FONT][/FONT] turn off but starter will not engage.
Turning key to the off position still leaves radio on with driver door open. I suspect this is what caused the [FONT=inherit !important]][FONT=inherit !important]battery[/FONT][/FONT] to drain, when it should be off it still supplies power to accessories.
Used a different ignition key to make sure that it simply did not read the resistor pellet wrong.
After removing key found that you can turn the ignition switch lock cylinder into all positions WITH NO [FONT=inherit !important][FONT=inherit !important]KEY[/FONT][/FONT]. Used the tip of the key and was able to turn the metal part of the switch where the key is inserted simply by twisting the metal lock cylinder clockwise.
Pulled codes and got the following codes:
BCM B2721 H, B2722 H, B2723 H C VATS codes
LDCM U1096 H
RDCM U1096 H
RFA U1255 H
Suspect ignition switch lock cylinder and/or the actual electrical portion behind the cylinder. Can the interlock cable to the shifter be causing the reason why [FONT=inherit !important][FONT=inherit !important]the[/FONT][/FONT] will not return completely to the OFF vertical key position?
Should I try the VATs relearn procedure (3 times ignition on then off then on (10 minutes at a time) as the battery was dead for some time or will this screw up things worse than they are now?
Can anyone shed light on the cause and fix for this problem?
Now the car starts
UPDATE:
Original problem was discharged battery. When I tried to start the car had moved shift lever out of PARK. This is why key was not vertical. Was able to remove key and turn tumbler without key in slot. When I put shift lever in PARK was able to return lock cylinder to vertical position. Once in this position it will not turn unless the key is inserted fully into the cylinder.
Cleared all codes and tried to start vehicle. Car started but still had the passkey code (B2723 H).
Cleaned key pellet with brake cleaner and restarted car.
NOW NO CODES SET.
Leaving battery on a charger tonight to see if I can fully charge battery and then will check for excessive parasitic drain.
Would like to bypass the pellet sensors in the key cylinder.
Have proper resistor value. Can I get to the fine white wires and [FONT=inherit !important][FONT=inherit ! important]connector[/FONT][/FONT] coming from the lock cylinder without disassembling the instrument panel?
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