Ignition lock cylinder

[drake13]

Hello, I had a post on here awhile back about my security light coming on and car not starting until it reset itself after about 3 or 5 minutes when the light would finally go out and car would start then. Well everyone agreed that after trying both sets of keys that it must be within the lock cylinder. Well i just replaced it today with one from advance auto parts but it doesn't have the VATS on it like the original does. After installation the car won't start at all and the security light now flashes and will not reset itself to start at all....Sooooo, i was wondering if i have to unhook something on the igniot switch that has to do with the VATS feature or if the replacement cylinder is going to have to have VAts with it !

I need to fix it this weekend and the parts stores are not sure of this question and all the chevrolet dealerships are closed til monday. Would love to have an idea from someone !! Thanks for reading !

[CLWILSON]

When my 91 started doing this I found out that the way the VATS works is that the two contacts inside the lock cylinder send a resistance reading to the ECM. I found out that you can bypass this by measuring the resistance on the chip in the key and then cut the wires that come off the ignition and solder in resistors equal to the resistance in the key to the two wires, creating a loop back to the ECM. This makes the ECM think that the right key is in at all times. The down side to this is that you no longer have the protection of the VATS. The wires in mine for the VATS were in a orange harness, but be sure that they are the right because you don't want to mess with the airbag wires, mine are in a yellow harness.

Hope this info helps

[N20LT4Bird]

CLWILSON is exactly right. This is the same thing you do when you install a remote start on a car with VATS. Just measure the resistance across the key and go to radio shack and get the same resistor and splice it in. Very easy.

[Rob B (shoebox)]

Replacing the lock cylinder with one that had no wiring to read the key, didn't accomplish anything and as you see now, it does not have any chance of satisfying the VATS module. You can use the resistor method like was suggested, but just beware that it makes it easier for someone to steal your car. You should be able to unplug the VATS wiring instead of cutting it, so you can insert your resistor(s). Here are key resistance values and how to read the key.

[tabahr]

Just out of curiosity.... If you were replacing the cylinder to fix the VATS problem why did you put in a non vats cylinder??

[N20LT4Bird]

Originally posted by tabahr
Just out of curiosity.... If you were replacing the cylinder to fix the VATS problem why did you put in a non vats cylinder??

Yea, I missed that in the original post. He could have wired in a resistor to bandage his problem to begin with.

[spoulson]

How do you replace the ignition lock cylinder? If it involves turning the switch, then what do you do if you can't turn the switch with the key in it? This is on a 98 T/A.

I think I've damaged my ignition switch by forcibly removing the key while it's in neutral, without knowing. In the process, I think I've damaged something and at this point the switch does not turn with the key in it! So tomorrow morning I will be calling around for parts, and will keep the VATS feature in mind, but I don't know how to remove and replace.

Any tips?

[tabahr]

You do not need to turn the cylinder to replace it. You will, however need to remove the steering wheel. Special tools like a wheel puller and snapring pliers are required. I suggest getting a haynes manual and following the instructions for lock cylinder replacement.

[stryker20]

quick question, I'm having the same problem, but I dont want to buy a new ignition lock cylinder b/c Im having an aftermarket alarm system w/ keyless start installed soon. Where exactly do I splicing in the resistor is it in the acutal ignition cylinder?

[Rob B (shoebox)]

Originally posted by stryker20
quick question, I'm having the same problem, but I dont want to buy a new ignition lock cylinder b/c Im having an aftermarket alarm system w/ keyless start installed soon. Where exactly do I splicing in the resistor is it in the acutal ignition cylinder?

At the base of the steering column you will find a small 2 cavity connector with two white wires coming from the column and wht/blk and ppl/wht wires going to the VATS. Unplug and then insert resistor on the side with the colored wires that goes toward the VATS.

[ZMAN_DIEHL!!!]

when i changed mine the two wires were wrapped with orange insulation.
ALSO do not go to a parts store and buy the key and lock cylinder
you have a 1 out of 10 chance of getting the correct resistance factor! I have had my coulmn apart twice once for the ignition lock cylinder because of a broken wire (white connecting wire) and the second time my start switch in the middle of the column went up in smoke and took my wire harness with it
I also suspect the alternator which was overcharging because of this took out my power window motor also. It is too coincidental that it all happened at the same time. WIRES CAN BE A MAJOR PAIN IN THE WALLET AND THE BUTTCHEEKS!!Good luck with Pass-Key. I would recommend bypassing the system anyway and leave the wires down in the dash somewhere with the old key soldered to it and then you can just go out to autozone and buy the non-VATS, el cheapo!! saves about half the over all cost and seriously increases the life of the lock and tumbler assy, as because you no longer have to worry about stressing the little wires out everytime you start it

[spoulson]

I managed to replace my lock cylinder just fine. I got the proper cylinder from my local dealer for ~$50, and a key with the right resistance code for ~$30. They have a machine that you put your old key in and it'll give the id of the pellet so they can give you a replacement blank to get cut.

I carefully ran the orange-wrapped wires and connector down the outermost part of the column, where it's supposed to follow, but then didn't fish it through the rest of the column (behind the panel) because the wiring and covers are too tight and I didn't want to risk breaking anything. But you can't see the orange wire once you bolt up the under-dash cover.

Worked great when I finished. It's too bad Haynes doesn't have any instructions doing anything further than removal of steering wheel. Having not done this before, the steering column was a total mystery at first. Here, I had to buy a steering lock plate tool and snap ring pliers to remove the lock plate. Then a set of torx screwdrivers to remove the turn signal mechanism. Then once out of the way, you unscrew and remove the torx pin holding the lock cylinder in place. Reverse with the new lock cylinder and I was back in business.