TripleBlack89

I've managed to lose the keys to my '89. After a period of frantic searching, I decided that I'd best get them replaced. Title in hand, I march off to my Chevy dealer, and they do "the lookup". Well, their report comes back with the codes for cutting the keys, but no information on the resistor value for the VATS key. At first, the guy at the Parts desk suggests that I don't have VATS on my car, but a quick check with one of his co-workers confirms that yes, even in 89, VATS was there. With that partial information, they can only cut me a door key. I take that home and it works fine, but all that does is confirm that I haven't locked the keys inside.

So, that's the story - here's the question.

How do I "read" my Corvette to determine which of the 15 keyblanks to use?
I have a volt/ohm meter, and I also have the chart of the 15 resistance values(1=392, 2=523, etc), so I could read the keys (IF I HAD THEM!) but I don't know how to read the CAR.

Thanks !

Tom Piper

If you have an old key, you can read the key "pellet" with an ohm meter and find out which one.

If you don't have an old key, the GM dealer is supposed to have an instrument that can be connected to the CCM to read the key information. As far as I know, only the GM dealer can do this.


Tom Piper

TA

Here's a link where you can purchase the instrument needed for $75, but I'd think a dealer should have one
http://www.gordonkillebrew.com/pages/800737/index.htm

tuband

OUCH! :( Sorry to hear of your predicament.

Guess this is a wake up call for everyone to be sure to have a working spare set of keys. Not a bad idea to have the keycode recorded somewhere to.

Hope you get everything solved soon.

DaveD

Do a search on 'vats bypass' in the archives. All kinds of info on which wires on the column are for the vats and how to get the car started.There are even kits to bypass it (at least that would get you started and running)Seems since you have what each code equates to resistance wise that the easiest approach might be to go to radio shack and buy resistors that are fairly close and try them (there are only about 15 of them if I remember right). or maybe get a 'pot' from radio shack and set it with your VOM to one of the chioces and try it, set it to the next choice, try it, etc till it starts.

Good luck. Let us know how you finally get it started.

Preacher

If the dealer can't do it :rolleyes: , any well-stocked locksmith should have the tool to decode the car.

I don't know where you are but, if by some small chance, you are in central California, You can go to Keylock Locksmiths in Grover (Ask for Charles) or to Santa Maria Lock & Key in (duh) Santa Maria (ask for Karl). Then there is Paso Robles Lock & Key.... (Jim's an odd bird, but does good work)

Good luck!

Steel Blue 91

:iagree: The dealer SHOULD be able to decode the car. The CCM stores the VATS value and makes sure it matches the key pellet when in the ignition. From that they will be able to cut a key with a matching resistance value.

kittmaster

:iagree:

Tom Piper

For anyone that doesn't have a spare key in a safe place (I have two spare keys and still did this), I suggest reading the "pellet" resistance of your key now with a digital ohm-meter for future reference. Could save you some headaches and $$$ down the road.

Tom Piper

TripleBlack89

Thanks for the suggestions - Keep 'em Coming, because none of them are quite what I'm looking for. If I could put my hands on a key to read the pellet, I'd just start the car with it! I'd read it with a Volt/Ohm meter years ago, but didn't write it down.

The dealer told me that he could read the code, but the car would have to be towed in.

Is there a way that I can read the resistance value out of the VATS module (wasn't a CCM until 1990) without having the car towed to a dealer? Could I pull the under-dash computer and have it read? The car's pretty tightly parked in a garage, and I'm concerned that having a tow-truck try to extract it will cause serious damage. It's a tight angle garage.

By the way - I seriously advocate having an extra set of keys, AND reading the pellet on your VATS key, writing the info down and keeping it safe somewhere. The database *DID* have correct information about my car's keys, but not which VATS code - with only partial information, I've still got a car I can't drive ! !

frank moran

a dealer or locksmith can do the decode it, there are 13 or 15 different pellets, try this, remove the hush panel and you should see 2 very small wires coming down from the ignition switch, disconnect that connector and take some resistance ohms readings on the harness side, not the switch side. Match that up with the designation for that key # and resistance value. See if that does it, if not a LS or daler can decode it. The tool takes some time between readings, but try my suggestion, let us know.

Rex Ruby

Set up some resistors to be able to duplicate the 15 possibilites.

Under the dash and steering column disconnect the 2 thin white wires, should be a disconnect plug there.

Set up the resistors for the first possibility, at the plug, on the side that goes to the computer, attach one side of the resistor set up to one of the white wires and the other side to the other white wire.

Use the key to try to start it. Keep going with the different combos of resistance till it starts. Just wait min of 4 minutes between tries due to VATS lock out when the wrong resistance is present.

That should work, no towing or locksmith service call :D :cheers:

TripleBlack89

[QUOTE(snip)]

... Use the key to try to start it.

[/QUOTE(snip)]

KEY? What key? :U If I had one of those.... I wouldn't be in this spot ! !

Steel Blue 91

I think what he is referring to is the key you can have cut by the dealer without the pellet. He has a good idea. Have a key cut using the VIN, just have it cut without any pellet. That will allow the lock cylinder to turn as you check the resistors.

OR

Have a key with pellet cut for each VATS resistor level (there is a list of 15 different resistors somewhere on the forum or in a service manual). This could be a little on the expensive side due to the cost of a VATS key.

Rex Ruby

I guess I missed it in your post. I thought you had a key w/o the pellet. I re-read it and see you only had a door key cut.

The dealer should be able to cut you one w/o the pellet. If not buy a new lock cylinder w/ any resistance key. Maybe you'll get lucky w/ the right resistor value. If not then you'd have to use my above posted method.

87SAM

Here's a list of possible pellet values I got from another forum member.

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

GlockLT4

Yup, this is all you need.

frank moran

you cant just buy any key with a pellet in it, the key the car was started with at the factory leaves its resistance print in the theft computor, the comp will only recognize that reistance. Unless you have the key code or by wild chance the dealer has them (gm records only goes back to 90) you will have to have a key cut or as suggested replace the lock cyl to establish a key cut BUT you still need to decode the vehicle for the pellet.....resistance. Most locksmiths and dealers have the decoder

TripleBlack89

<<GM records only goes back to 90>>

...Yeah... I'm painfully aware of *that*. They found the info for the physical key cuttings, but not the resistance value. :banghead:

Aggravated4life

Is the dealer pulling records off a computer? If so,tell them to go into their archives and look in their books.Back in the 80's and early 90's we used these books at the GM parts department and usually they get saved somewhere.Unsure if that will help you but if theres some book laying around with the vin numbers and resistance types in there,they can help cut a key.
Too bad you dont remember the number...if they were able to let you try out a bunch of keys,that would be cool,but theyve always charged so much money for that.

Im glad to this day Ive always remembered my pellet value.It was really easy for some reason.And i have spares...whew.May be able to dow hat rex said and try out resistors somewhere and see if it helps.
Good Luck and hope it works out for you somehow.