can VATS Security System be disconnected on a 91?

[drkjr]

My security system is giving me a major problem, whenever I drive my car, and shut it off, I have to disconnect the battery for around a half hour to drain VATS memory in order to start it again, I think there is a loose wire in one of the door handles, but am trying to sell the car and don't want to put any more $$$ into it...is there an easy way( or not so easy) to disconnect the VATS System?

Or any other ideas?

thanks!

 

[drkjr]

anybody ???

 

[Moonunit 451]

I'm sure it can. Go to my profile, pull up my topics or posts or whatever. Go to my second post and start reading. EVERYTHING you need to know is right there, and I did it on my 86.

 

[drkjr]

can you tell me the name of that particular post? you have 20 pages of posts! Thanks!

 

[Moonunit 451]

It started at like my second ever post. Don't have the time to search it for ya, just go to the 1st page.

 

[drkjr]

I have looked all over for that post, i think they cap you at 500 posts (20 pages), because i can't find it anywhere!

Thanks anyway...you wouldn't happen to have it saved on your computer, would you?

 

[Moonunit 451]

Hey I'm really sorry, but I was running flat out yesterday. If you use the search for VATS you'll find a ton more stuff. I found this in about a minute searching for topics created by.....me. http://www.corvetteactioncenter.com/forums/showthread.php?t=23029

 

[drkjr]

ok, i was just told that maybe the car is storing a security code in the memory, that triggers after every drive, and is only cleared by disconnecting the battery like I've been doing...does this make sense to anyone, and if so, any answers? Is there any easy way to clear that code if that IS the problem?

 

[Moonunit 451]

I doubt it. Did you read the info? I'm surprised no one else is on this for you. There was a LOT of help for me. I think you should fisx the VATS problem or bypass it. You can temporarily bypass it to rule it out. It doesn't cost anything but a couplw bucks.

 

[jmccloud]

VATS bypass

This came from an old thread.


GM No-Crank in vehicles with

Vehicle Anti-Theft System (VATS)

A No-Crank condition in GM vehicles with Vehicle Anti-Theft Systems may be caused by either a bad igintion key or a

problem in the ignition switch/VATS wiring harness. (Switch/harness assembly problems seem to be more common than

key failures.)

Test 1) Check the ignition key. Each key contains a resistance pellet. Remove the key and check the pellet’s resistance.

The chart below shows possible resistance values for ignition keys. If the key resistance matches one of the chart values,

go to Test 2. If the key’s resistance value doesn’t match one of the values in the chart, replace it with a new one. Your

GM dealer can provide part number information if you give him the VAT module identification number.

Test 2) Insert the ignition key in the ignition switch. Remove the lower dash bezel. Locate the two-terminal white connector

near the base of the steering column, and disconnect it. (See the next tip for a schematic.) Insert your ohmmeter

leads across the terminals of the connector half containing the white wires and measure the resistance. The resistance

value measured across the connector should match the key resistance. If it doesn’t, then the problem is in the switch/

harness assembly. Replace the assembly.

Resistance Value Chart for GM VATs (Lists possible resistance values, including acceptable ranges)

• 402 ohms (acceptable range 386-438)

• 523 ohms (acceptable range 502-564)

• 681 ohms (acceptable range 650-728)

• 887 ohms (acceptable range 850-942)

• 1130 ohms (acceptable range 1085-1195)

• 1470 ohms (acceptable range 1411-1549)

• 1870 ohms (acceptable range 1795-1965)

• 2370 ohms (acceptable range 2275-2485)

• 3010 ohms (acceptable range 2890-3150)

• 3740 ohms (acceptable range 3590-3910)

• 4750 ohms (acceptable range 4560-4960)

• 6040 ohms (acceptable range 5798-6302)

• 7500 ohms (acceptable range 7200-7820)

• 9530 ohms (acceptable range 9149-9931)

• 11800 ohms (acceptable range 11328-12292)

Silver

Bullets

Temporary Fix for GM No-Crank in Vehicles

with Vehicle Anti-Theft System (VATS)

Experience suggests that VAT

ignition key failures are less

common than no-cranking conditions

caused by switch/harness

failures.

If you need to start a car to get it

into the shop, try this:

• Remove the ignition key and

measure the resistance of the pellet

in the key.

• Drop the steering column bezel

and disconnect the white wire

connector.

• Connect your sensor simulator across the terminals of the harness connected to the VATS module and “dial in” a

resistance equal to the key pellet resistance, or simply insert a fixed resistor of the correct value.

This bypasses the key/harness and, in many instances, it will allow you to start the vehicle and drive it into the shop.