C4 Theft Mode Lockout
Thread Starter
2nd Gear
Joined: Apr 2011
Posts: 2
Likes: 0
C4 Theft Mode Lockout
Just got a call from the Chevy dealer and he says I have to pay $550 to have my ignition cylinder and ignition key replaced because my car has been programmed to the anti-theft mode.
Background: Took my car to a Lube shop and after they programmed out the Oil Change light indicator, the car would no longer start.
If you short acoss the starter terminals, the car starts but dies within 3 seconds (repeatably).
Found on line that this vette has a anti-theft system that prevents power to the starter relay and the fuel pump when in theft mode.
So now the question is...how to unprogram the theft mode. Can't believe that I really have to replace the ignition cylinder and key to fix this. I would think if it can be programmed ON, it can be programmed OFF, but the dealer mechanic says no.
Anyone got any ideas for a fellow vette brother that doesn't like getting robbed by the Chevy dealer mechanics?
Background: Took my car to a Lube shop and after they programmed out the Oil Change light indicator, the car would no longer start.
If you short acoss the starter terminals, the car starts but dies within 3 seconds (repeatably).
Found on line that this vette has a anti-theft system that prevents power to the starter relay and the fuel pump when in theft mode.
So now the question is...how to unprogram the theft mode. Can't believe that I really have to replace the ignition cylinder and key to fix this. I would think if it can be programmed ON, it can be programmed OFF, but the dealer mechanic says no.
Anyone got any ideas for a fellow vette brother that doesn't like getting robbed by the Chevy dealer mechanics?
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Doubt it. Sounds like a mechanic's scam to me, but I don't know everything about every year. Who knows what your whatever year can do!
Melting Slicks
Joined: Feb 2011
Posts: 2,322
Likes: 6
From: Los Altos CA
This comes up often here. Do a search for VATS & you may learn more.
Normally, as far as I know, the VATS system only locks you out for 4 minutes or so, then should reset.
Do you have another key to try? Maybe the key you gave to the mechanic is bad. I have two keys & one is so worn it triggers the VATS. The previous owner, i.e. Dad, got a free fuel pump because he left the bad key with his mechanic who, not understanding the VATS system, replaced the pump.
Normally, as far as I know, the VATS system only locks you out for 4 minutes or so, then should reset.
Do you have another key to try? Maybe the key you gave to the mechanic is bad. I have two keys & one is so worn it triggers the VATS. The previous owner, i.e. Dad, got a free fuel pump because he left the bad key with his mechanic who, not understanding the VATS system, replaced the pump.
Racer
Joined: Oct 2007
Posts: 294
Likes: 0
From: High Desert Southern California
This sounds crazy. I recently had a problem with the antenna and replaced a few fuses that were missing. I fixed the antenna problem but created an alarm problem. The alarm went off all the time, I think the car automatically locked and as you said, could not be started. My solution was either to pull the offending fuse or make sure I lock the car with the remote and unlock it with the remote when I am ready to go. That seemed to reset everything. I am interested in what other will have to say. There is more to my story but the short of it was to lock and unlock with the remote.
Racer
Joined: May 2007
Posts: 301
Likes: 0
From: Flint MI: Birthplace of the Corvette
I'm thinking you have a VATS problem. A thin little wire in the steering column that goes to the keyswitch probably broke. My guess is that the oil change lamp reset had nothing to do with it and the timing was only coincidental. The fix is either a new keyswitch which involves taking the steering column apart and could explain the $550 cost or you could bypass the system with a 20 cent resistor. Here's a link to the procedure. (I've done this on several vehicles. If you get the correct resistor value, it works great!)
http://vats.likeabigdog.com/
You could add the resistor temporally and see if it fixes your problem.
Good Luck!
Dave T.
http://vats.likeabigdog.com/
You could add the resistor temporally and see if it fixes your problem.
Good Luck!
Dave T.
Last edited by ecorse66; Apr 26, 2011 at 09:26 PM.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
1) There is no such thing as to "un-program the theft mode".
2) When you say won't start, I take that to mean it won't crank (turn over).
Hears the only information that makes any sense in regard to the stated facts.
VATS, or know as the pass key system is part of the anti-thief system. If the key pellet is not read properly by the CCM (where VATS lives), it will not activate the start relay.
Either the key pellet is dirty or defective (try another key). Or…..and this is what the dealer is really saying, the lock cylinder where there are 2 contacts that connect to the key pellet are defective. If the lock cylinder is bad then the key can't be read, then VATS can't turn on the necessary systems.
This is possible but I don’t think this happens much. You can get the resistance of the key pellet, find the 2 wires at the bottom of the steering column, and install a equal value resistor. Then turn the key in the cylinder and see if it starts.
The other side of the coin is it's not a VATS related problem at all. If the neutral switches are not making contact depending if it is standard or auto, the engine won't crank either. Do you think the lube shop busted a wire, connector or dislodged something??
2) When you say won't start, I take that to mean it won't crank (turn over).
Hears the only information that makes any sense in regard to the stated facts.
VATS, or know as the pass key system is part of the anti-thief system. If the key pellet is not read properly by the CCM (where VATS lives), it will not activate the start relay.
Either the key pellet is dirty or defective (try another key). Or…..and this is what the dealer is really saying, the lock cylinder where there are 2 contacts that connect to the key pellet are defective. If the lock cylinder is bad then the key can't be read, then VATS can't turn on the necessary systems.
This is possible but I don’t think this happens much. You can get the resistance of the key pellet, find the 2 wires at the bottom of the steering column, and install a equal value resistor. Then turn the key in the cylinder and see if it starts.
The other side of the coin is it's not a VATS related problem at all. If the neutral switches are not making contact depending if it is standard or auto, the engine won't crank either. Do you think the lube shop busted a wire, connector or dislodged something??
