Here's my situation. I managed to lose the one and only set of keys I have more 91. After jumping through some hoops I realized that The key code on file at GM is not correct for my car (someone must have changed the lock cylinder over the years) and their is no VATS code on file. Fast forward to today.............. I've changed out the lock cylinder so now I have a key that will, at least turn the cylinder, but of course I still don't know the VATS resistance in my car (the lock that comes with a new cylinder and key that has no resistor). I have a pretty good idea of what I need to do to get the car running but I have a few questions.

I know that for people that have their VATS key you can simply measure the resistance of the leads that come from the VATS wiring. Now in my situation this obviously wouldn't work as there is no resistor in the key. I believe I can wire up resistors (of each of the 15 possible VATS codes) and insert them into the wires that the VATS key wire plugs into. Using this method I'd just try each possibility untill I found the correct one and the car started.

Now my question...........Is it possible to measure the resistance across the wires where my VATS key wire plugs in? The two wires coming from the key are white. They go into a connector that leads to, I believe a brown and a brown/white wire. Can I measure the resistance across the brown to the brown/white wire?

I know that trying each of the possibilities will work (or at least I think it will), but if it is possible to measure the resistance across the wires it would save me some time.

Thanks for any input.

Tom

BTW here's a thread that goes over my whole dilemma

http://forums.corvetteforum.com/show...87&forum_id=34

 

No, that willn't work. You can do what you suggested by trying the 15 different values for the key resistance. Make sure you wait a full 3 minutes between trys though, because once the vats sees a wrong resistance it starts a delay so that even the correct setup is not going to work and a new 3 minute delay will be started. Here's a picture of my vats bypass. I have a GM pigtail that plugs directly into the stock plug, so I enable the vats function when I want.

 

In a work, NO. The value of your resister is programed into you system, and is not a physical device that can be read directly. What you need is a device called a "Vats Interigater". It plugs into the harness where your lock now plugs. Since you just changed your lock, you know where that is. The interigator is an elevtronic or mechanical device whick has the capability of providing all the various resistances one at a time. When a start, using the wrong resistance is attemped, your on-board computer will time out for three to five minutes (It varried from year to year so I can't remember exactly).

With the interigator hooked up, you simply set it to imulate the first resistance, then turn the switch with the key. If the car starts, your very lucky. If it doesn't, you wait for the security system to time out, set it to the second resistance, and try it again. (By-the way, don't waste your time with #1 resistance. It was reserved for police and fleet cars.) Anyway, you continue going through the resistances until you hit the one which lets it start. When you identify which one it is, you take the key which came with your new lock to a locksmith who sales vats keys and copy it onto a key with the correct chip.

Where do you get a "Vats Interigator"??? You wouldn't want to buy one, (there like $400.00+) Most locksmiths who do automotive have one. If you have lots of patiance, you could buy the resisters at RadioShack and make up a set of aligator clips atached to the pigtail which was part of your old lock(after you cut it off the lock). It would give you something to do while waiting for the security system to time out.

 

If you don't care if you have the VATS or not, there is an easier way. Get a new chip burned for the ecm that disables it. This was an option I had when I got my chip burned. I kept the VATS but I know they can disable it like this. Talk to "ski-down-it" about this he might cut you a deal.

 

It is not a good idea to defeat VATS because 99% of thefts are done by bashing the column and jumping the ignition.
VATS makes you wait 6 minutes if you try to start without the correct pellet. You can reset the ECM with the single wire connector by the battery so you don't have to wait 6 minutes, but of course you will have to reset your clock and radio presets.

 

Which connector do you mean and are you sure this works? Thanks

 

By the right side of the battery is a single wire with a connector. This wire powers the ECM and when you disconnect the connector only the ECM resets so you don't have to redo your radio presets and so you don't have to wait 6 minutes between VATS detecting a wrong pellet.

 

TA, this post might help you... it's in the archives and I"m not sure where the images are for the post... but the info is in the service manual. If you really need it let me know and I can look it up.

You can find out which one the CCM is expecting with this method. No original key is needed.

http://forums.corvetteforum.com/show...m_id=48&arch=1

 

Hey Craig, thanks for the info. I actually just got the car started a couple hours ago. I ended up simply duplicating the possiblity of each resistance and luckily on the third try I got it right and the car started. I actually should say that it was the third try today as I tried all 15 possibilities yesterday, but learned I was doing something wrong. It was a great feeling to hear that engine roar to life!

 

do you have a list of the 15 resistances you used?

 

Yep, here's all 15 possiblities

Pass Key Codes:
Key……….…...Ohms
.1………….….... 392
.2………….….... 523
.3……………..… 681
.4………….…..…887
.5…………….…1.13k
.6…………….…1.47k
.7……………….1.87k
.8……………….2.37k
.9……………….3.01k
10………………3.74k
11………………4.75k
12………………6.04k
13………………7.50k
14………………9.53k
15……………..11.80k


I used a pentiometer (sp?) to set up the different values.

 

So many vats problems, I just finished posting in the other VATS related thread...

There's a VATS interrogator too, I didn't see anyone mention that, so if you had it towed to a dealer they could probably tell you what it is? I was lucky enough to ave my key, so all it cost me was $0.99 and whataver gas for a trip to radio shack...