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Ignition switch position almost into ACC position OFF-will not start

I love my Chevy Chevette!
Posts: 1
Joined: 04/14
Posted: 04/15/14 09:56 AM

Tried starting 98 C5 yesterday, battery was completely dead. Charged overnight and had 12.84 volts 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 slot 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 accessories 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 battery 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 KEY. 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 the switch 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
Original problem was discharged battery. When I tried to start the car had moved shift lever out of PARK. This is why key slot 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.
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 connector coming from the lock cylinder without disassembling the instrument panel?  

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My first time was in a Chevy
Posts: 140
Joined: 10/13
Posted: 04/15/14 06:06 PM

there is a LOT of info on how to bypass the PASSLOCK  security system..

the battery has to be completely charged and a battery charger hooked up or another car idling next to it with jumpers hooked to that car.. it does not have to rev..

the car should start one time after 10 minutes.. set you watch.. when the security light flashes at the 10 minutes on .. start the engine.. that bypasses the system to get the car started.. will it work from there???

i saw an interesting article just the other day on the passlock system..   i will have to look around for it.

i think the C5 models and C6 models have a motor driven column lock device.. yes. the shift interlock cable can get out of adjustment and prevent the full removal of the ignition key in the LOCKED position.

please.. when/IF.. you dig into the ignition lock cylinder.. remove your ignition switch.. either replace it.. or on a big white towel.. take it apart carefully.. and burnish the silver contacts that are in it..  burnish is the rubbing of the surface to remove any oxides but not sanding or filing away the surface..  a little sanding will probably work..

there are articles on this exact issue..

and.. please DON'T over charge the battery..

depending on the charger it is fairly easy to ruin a good battery.. if its been discharged for more than a week or two.. its probably damaged internally by charging.. it hardens the surface of the plates.. hardens the sulfate crystals..

usually i use a 10 amp charger..  when i hook it up.. it will usually charge a few amps more than 10 amps for a few minutes..  then it will drop to a steady 10 amp charge..    once it starts dropping under 10 amps after being stable at 10 amps for 20 to 55 minutes..  its charged..

totally discharged batteries should be recharged over several days on a current limiting adjustable voltage power supply..   automotive size batteries.. 1/3 of an amp at 17 volts for 2 days.. this is when the battery is found discharged. only a voltmeter used to check it.. and that nobody has jumped the battery or tried a conventional charger.  i have used this for years..  these current limiting power supplies are not cheep..usually over 160 bucks..  so its not the average thing. but i use it to power various parts and equipment..   if you have one.. clips separated.. set voltage to 17 volts DC.. touch clips.. adjust short circuit current to 1/3 of an amp..  disconnect clips from each other.. hook to battery.. walk away for 2 days..  this is for batteries that have been found with voltages below 11.5 and have been sitting for a while..

it is is a VATS System instead of a passlock that other 98 GM cars and trucks use..

pick up one of these from your local radio shack store..  its in their parts drawers..

10K-Ohm 15-Turn Cermet Potentiometer/Trimmer
Model: 271-343  | Catalog #: 271-343

attach it to the body side of the ignition switch pigtail..  using the first and second wire or second and third..  but not the first and third..

this will allow you to duplicate the resistor key value perfectly.. using just an ohm meter and a tiny screw driver..  

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