rwmj5

I've been reading a few of the VATS related threads on here but I am still trying to figure out the best way to attack the problem my car has. I have a 93 Z28 six speed. after owning the car several months with no issues, I started having problems starting the car. I drove it down to a garage to have an unrelated issue checked, and about 10 minutes after I got there we tried to start it but it just would not fire. they determined that the fuel pump was fine but it was just not getting power. they said the theft deterrent module was bad and that I would need to get it towed to a dealer so they could swap it out program it etc.

whats the best/easiest way to get around this? from what I gathered, there are two parts to the VATS, one keeps the starting system from engaging and the other cuts power to the fuel pump. apparently the fuel pump is not getting the signal to turn on and thats the reason they think the vats module is bad.

what sort of work would be required to get at the current vats module and replace it with a good one? would I be able to install one of those signal generating bypass boxes without having to get all the way to the actual vats module?


I trimmed this post down a bit from the original version. any info anyone has on how to workaround this or what sort of effort would be required to replace the vats module would be appreciated.

thanks

shoebox

Was the security light ever on? If not, it's probably not a VATS problem. It might be the ignition switch.

rwmj5

I remember the light being on, but I can't remember if it was blinking. the engine will crank forever with no problem, its just that the fuel pump isnt getting powered on

rwmj5

so anyone know how to get around this VATS system?

rwmj5

anyone at all...

shoebox

There are many, many threads about the VATS system in the general tech forum. I guess people are tired of answering questions about it.

rwmj5

hmm I had not even looked in the general tech forum. I guess I had thought this was the onlyone that would involve engine starting trouble. yeah there are a lot more posts on vats in there. I'll try going through som of them. thanks

SweetZRag

If I recall, and I could be wrong, the VATS system only prevents the starter from cranking. I don't believe it affects the fuel pump in any way (again, I could be wrong). I think if you are cranking, the VATS system is fine.

I haven't looked at the schematic for quite a while. If anyone knows I am wrong, please jump in.

Jeff

shoebox

The VATS will also stop fuel to the engine.

Dave89IROC

by shutting down the injectors, but not the pump, IIRC

ACE1252

If the security light was solid, then either your key or cylinder key lock is wearing out. If it's your key the replace it(just start using your spare to test it). If it continues to do it, then do this until you can replace the cylinder lock....
http://shbox.com/1/vats_bypass.jpg

Here is a bunch of other useful info on Shoebox's site....
http://shbox.com/1/how_tos.html

rwmj5

I have heard from a bunch of different places that there is a starter/fuel injector cutoff, and a separate fuel pump cutoff. Ive also heard a couple people say that their actual vats module "Theft deterrent module" had gone bad, and after replacing that everything worked ok. I think If the problem was with my key, i would get the flashing security light, plus I dont think it would crank. I can get it to crank no problem, it will just never fire because the fuel pump is not getting powered. the mechanics tested the pump and confirmed that it is not receiving power, and that it works fine when they power it directly.

right now I'm just basically trying to figure out exactly how to get to this theft deterrent module to replace it because I think its bad, or if that would be a major pain, if I should just try to turn the VATS off in the custom tuning chip I am getting, or if that would even work if the module is messed up

Dave89IROC

check the fuel pump fuse/relay first, before jumping on the VATS module

rwmj5

here is a great question that I have never seen answered satisfactorily- Where the heck is the actual VATS/Theft deterrent module located?

I've heard all sorts of descriptions of "its sort of under the dash by the glovebox." I've heard "its on the left side of the glovebox". Ive heard the opposite: "Its under the dash to the right of the glovebox."

Where is it really located? I have seen no pictures of it or where it is located. People have said 'I swapped out my VATS module and everything worked fine' but there has only been ambiguous descriptions as to how they got to it. I've even seen people on here ask where it is, and the question was totally ignored. It seems to be a mystery for some reason.

So where is the theft deterrent/VATS module REALLY? Does anyone have any photos of its location, or even any photos of it by itself, or at least have a worthwhile description of where it is and how to get to it?

Guest47904

It's behind the dash between the radio and the glove box. It has a (in a 94) a green 16 pin connector from the harness plugged into it.

You needn't get to it however, to diagnose the problem. Simply read the resistance of your key pellet and get a combination of resistors that add up to that resistance. Unhook the orange wrapped 2 wire connector at the base of the column that connects to the key contacts. Put the resistor(s) in the connector leading to the TDM and try it. If the security light is still on, either the wiring to or the TDM is defective. At that point you will have to find the TDM. Simply buzz the wiring to prove the TDM is optafriggin.

The wires you're concerned with are purple/white and white/black. on pins B7 and B8. However, more than likely like most of us the key and or the contacts in the column are worn to the point it no longer makes good contact.

I like the resistor method my self. No more $30.00 keys and intermittent contact when you're away from home.