bigsticksupra

iTrader: (3)

Hello,

I was in the process of running wiring underneath the steering column for my shift light when I ran into a weird jumper thing that was tapped into a factory plug from the previous owner. When I removed the jumper, the car wouldn't crank. When I plugged the jumper back in, the car cranked and started fine. The jumper appears to have something underneath the shrink wrap, maybe a resistor or something? The car is all stock and runs great with no check engine lights or anything like that.

Anyways, does anybody know what is causing the car not to crank/start when the jumper is removed? I assume it has to do with whatever the factory plug wires to (what does it wire to?). I would rather fix whatever is preventing the car from cranking than to rely on this jumper from the previous owner. Thanks!



jumper from the previous owner connected to this factory plug underneath the steering column.

jumper. appears to have something underneath the shrink wrap - a resistor or something?

factory plug with the jumper removed. when the jumper is removed, the car won't crank.

WhiteBird00

iTrader: (4)

That is a VATS bypass. The previous owner created a jumper with resistor(s) matching the resistance of the ignition key pellet so that all key related problems (broken wires in column, worn out key contacts in cylinder, broken or missing resistor pellet in key, etc.) would be avoided. Best to leave it there since apparently your key or cylinder or column wiring is bad (the car won't start with the key you have).

bigsticksupra

iTrader: (3)

Thank you, WhiteBird00, your knowledge of these cars is awesome!

Hmm, so this is an interesting revelation for this new-to-me, all stock car. Is it worth fixing the VATS instead of bypassing it for theft deterrence reasons? I guess the fix would be a new ignition cylinder? I see HAWKS has new ones for $52. I searched VATS bypass and I see a lot of people doing VATS bypass for one reason or another. I guess its not that great of a theft deterrent if someone can just plug in a resistor into a plug that is easily accessible lol

If I leave the VATS bypass in, is there a better, more reliable/professional way to do it instead of just electrical taping a resistor wire in the plug?

With this VATS bypass in my car, does it change how I would wire in a kill switch per your post #22? https://ls1tech.com/forums/wiring-st...ow-wire-2.html

WhiteBird00

iTrader: (4)

Frankly, VATS was a useful system when it first appeared and it can still be useful in preventing joyriders from stealing your car, but these days it's only a minor annoyance for professional thieves because it's simple to bypass. Besides, most pros are more interested in your car for parts than for driving, so it's more likely to be towed than driven away.

That being said, VATS was not the most reliable system. Even just getting the ignition key resistor contacts dirty from being in your pocket could be enough to change the resistance and have VATS disable your car unexpectedly. Plus, as these cars get older, simple wear in the ignition cylinder could prevent solid contact in the VATS circuit. And there's always the old favorite - the tiny wires between the ignition cylinder and the connector near the base of the column are known to break. A VATS bypass eliminates all those possibilities of being left stranded somewhere unable to start your car.

The method used in your case is pretty standard. You could pretty it up by using heat shrink tubing or encasing the taped wires in some of that flex tubing for wiring harnesses, but those are just appearance options... the practical bit looks like it was done correctly other than it's normal to unplug the connector to avoid any extra wiring in the circuit which could affect the total resistance. In fact, I would bet that the wires in your column are broken because otherwise you would get a resistance change from your ignition key. That's likely why the bypass was done.

Having a VATS bypass installed as it is will have no affect on any kill switch you might want to install. The bypass only shortens the resistor circuit loop used by VATS by eliminating the part that's in the steering column. It does give you an opportunity to combine a kill switch with the VATS bypass by putting the resistors inline next to your new kill switch so that the circuit is open with the switch off and flows through the resistor with the switch on. That could be considered a more "professional" installation - or at least a more hidden one.

bigsticksupra

iTrader: (3)

Thanks for all your help, WhiteBird00! I've had 4 previous F-Bodys and I guess I never knew VATS was an issue for many people, but then again the cars were a lot newer when I had them. I found a locksmith shop online that sells the OE GM lock cylinder (STRATTEC?) and will cut you the new keys for it with the proper GM key according to your car's BCM VATS resistance. I think I'll do that since it'll be a straight forward install with everything ready to go. If it messes up again in the future, its VATS bypass forever

Thanks again!

bigsticksupra

iTrader: (3)

Following up with this thread, I ended up buying the OE GM ignition cylinder (STRATTEC) from an online locksmith. I measured the resistance of my original keys and they cut new GM keys with the same resistance for the new ignition cylinder. As WhiteBird00 correctly predicted, the little wires coming off my original ignition cylinder were broke which is why the previous owner had to do the VATS bypass. I followed the instructions by wssix99 (https://ls1tech.com/forums/general-m...mn-repair.html) on how to tear down the steering column and replaced the ignition cylinder and everything works as it did from the factory without the VATS bypass now. Thanks WhiteBird00 and wssix99 !



wire from the original ignition cylinder is broken

new OE ignition cylinder