the lovely VATS system.

[3.4_5-speed]

ive got a 94 camaro and the vats system decided to take a dump. my question for all of you is does anyone know how to properly send the correct signal to the PCM (powertrain control module) for the fuel injector enable, by bypassing the TDM (theft deterrent module)??

any advice is much appreciated!

[pocket-rocket]

I'm not sure if it would work on a 94 Camaro, but on a 96 Acheiva with a 97 GA PCM, it would allow the car to start with the PASSKEY (newer VATS system) harness from the column disconnected due to the system going into fail-safe mode. Is the system in a 94 Camaro the silly one with the resistor pill in the key? If so, measure it with an multi-meter, write down the resistance value, go to Radio Shack and buy some resistors the same resistance value, clip the wires under the column for the VATS and put the resistor in between them and the car will start, unless the VATS module itself is shot. Only do this if you don't mind pretty much disabling your VATS system, since it will no longer be reading the resistor pill in the key and would then start with a generic cut key instead of a VATS key.

[3.4_5-speed]

ya its the one with the pellet, the only thing is ive already got the resistor value, which is 6.04 k-ohmes. and ive went to radio shack and bought the resistors. however ive tested the lines coming into the TDM and theyre the correct values for the resistor pellet so i dont need the resistor. and i hot wired the theft deterrent relay which allows me to start the car but then it doenst keep running because the fuel enable is still locked out. the more and more i think about it it seems like it is the TDM that is faulty, and ive already priced it out from the dealership. they want like $300 for the module. im just not willing to spend that much for it. instead i would like to bypass the whole think, just trying to figure it out.

[robertisaar]

if the module itself died, then the resistor trick won't work...

you can setup a 555 to make a 50% duty cycle 50Hz signal and that will get the PCM to fire the injectors.

[pocket-rocket]

if the module itself died, then the resistor trick won't work...

you can setup a 555 to make a 50% duty cycle 50Hz signal and that will get the PCM to fire the injectors.

Well, Mr. Smarty-pants lol Knowing the key goes through thousands of key cycles in the lifetime of a vehicle causes the contacts in the lock cylinder to go bad, I was assuming it was the contacts that have gone faulty and not the actual module probably about 90% of the time.

Op, you may want to visit a you-pull-it yard. I bet you can get one at a fairly cheap price, and may even find more than one so you have a backup. I just hope it's in an easily accessed spot.

[robertisaar]

you would need to find one that's already setup for your current key resistance though... 1 in 15 chance of that.

they only go through their key learn procedure once.

[pocket-rocket]

you would need to find one that's already setup for your current key resistance though... 1 in 15 chance of that.

they only go through their key learn procedure once.

You got me there, I completely forgot about that part. Stuff like this makes me glad my cars have no anti-theft besides the locks, the alarm and my Ruger... Semi-auto FTW!

[robertisaar]

also, if the module is completely removed, you may have to bypass/delete the starter inhibit/enable relay that the VATS module controls. otherwise, the starter won't engage.

[3.4_5-speed]

if the module itself died, then the resistor trick won't work...

you can setup a 555 to make a 50% duty cycle 50Hz signal and that will get the PCM to fire the injectors.

the answer i was looking for! thanks guys, ill give this a shot and see how it does. how exactly would i go about doing that though? ive isolated the wire to the PCM that comes from the TDM but what needs to be done to it?

on a separate note i have gone to the yard and thought about the whole 1/15 chance of pulling the right module. and after pulling only one i realized that the work involved in pulling 15 was way to much to get involved with. i also have already bypassed the starter enable relay so i can get it to crank, just wont stay running cuz the fuel enable cuts it out.

[robertisaar]

wire it up so that anytime the ignition is in the on position, power is supplied to the Vcc circuit. setup the resistors and capacitors as shown, and connect pin 3 to the wire that goes from the VATS module to the PCM, since that is the circuit that the PCM monitors for the 50% DC, 50Hz signal. a 555 should be able to natively accpt up to 18 volts, so you shouldn't need any type of regulator in a 12 volt car.

i think that's all the specifics of it.

[cardana24]

If you don't need your vats system to function I have a bypass module that I used on my 3.4 swap before I had the bypass built into a wiring harness. It's just a three wire connection. Its the one that Baker sells. Just PM me if you are interested.

[tkoforpresident]

Or you can turn VATS off altogether like I did

[Schmieder]

Damn Robert, you are a smart one!

I did the resistor bypass and it worked just fine for me. I bet the hammers that contact the key resistor are bad. There is a way to test the required resistance on the controller, but I forget how. So whe you go junkyard diving you can pinpoint which one will match your key, if you want to keep the setup.

If the resistor mod works, make it to where you can unplug it and take the resistor set up with you. No one is starting that car w/o it.