The classic VATS problem on a '90 base
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Cruising
Joined: May 2020
Posts: 10
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From: Colorado Springs CO
The classic VATS problem on a '90 base
So I have encountered the classic VATS problem. Starter motor is good (works after a bypass), replaced the starter relay, so now we narrowed it down to the VATS system and I am prepared to do the good old resistor bypass. However, I am unable to be sure of which wires are indeed the VATS wires. I have been unable to find a wiring diagram for the VATS system/anti-theft circuit so now I am resorting to the power of the forum! I have heard several different colors of wires for the VATS system such as the blue and red, orange, etc. I am pretty sure my VATS wire is the large orange (that is stripped midway down to reveal two smaller white wires) transitioning to two small white wires which then transition into a connector that is harder than hell to take off. Is this my VATS cable?
Team Owner
Joined: Sep 2003
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So I have encountered the classic VATS problem. Starter motor is good (works after a bypass), replaced the starter relay, so now we narrowed it down to the VATS system and I am prepared to do the good old resistor bypass. However, I am unable to be sure of which wires are indeed the VATS wires. I have been unable to find a wiring diagram for the VATS system/anti-theft circuit so now I am resorting to the power of the forum! I have heard several different colors of wires for the VATS system such as the blue and red, orange, etc. I am pretty sure my VATS wire is the large orange (that is stripped midway down to reveal two smaller white wires) transitioning to two small white wires which then transition into a connector that is harder than hell to take off. Is this my VATS cable?
Last edited by WVZR-1; Jun 30, 2020 at 03:33 PM.
Thread Starter
Cruising
Joined: May 2020
Posts: 10
Likes: 1
From: Colorado Springs CO
Thanks, that looks to be the one! Would I solder the resistors on the double white wire or the purple yellow and white black wires? There's not much info on the real specifics that I can find.
Team Owner
Joined: Sep 2003
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Do you know 'for a fact' that you've a continuity issue at the column base? If you've not confirmed an issue that's created by continuity reading the resistance value you do that first. If there's an issue with the cylinder and wires then you could snip the wires going up the column add your resistor to that and it becomes a 'dongle' that will plug-in to the mating. Do your fabrication on the bench. Is the car an A4 automatic or maybe a manual M6. Confirming crank by just bypass and relay confirms maybe nothing. A4 neutral safety switch or clutch safety on an M6. I wouldn't jump to conclusions, If you've checked the resistance of the key maybe you consider the purchase of a correct 'dongle'! Maybe!
There ain't no 'classic VATS' - you either have an issue or NOT. By-pass key resistance is often a consideration.
Last edited by WVZR-1; Jun 30, 2020 at 05:40 PM.
Safety Car
Joined: Aug 2013
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From: Minneapolis Mn
Easiest way IMO to tell if the VATS system can read the resistor off the key is disconnect the connector on the orange wire, take a dvm and set it for ohms and connect it to the column side of the connector. Insert the key into the ignition (don't remember if it had to be in the on position or just in the off was good enough) and see if it's reading the key or not.
If you want to bypass the resistor, IMO the best solution is to buy one of the dongles that match the resistor on the key. You just need to plug it into the dash side of the vats wiring and you're done
I've done it so it's within the capabilities of virtually anyone. Hardest thing is to find the wire and all you need to do is look for the one with the orange wrap on it coming out of the bottom of the steering column.
If you want to bypass the resistor, IMO the best solution is to buy one of the dongles that match the resistor on the key. You just need to plug it into the dash side of the vats wiring and you're done
I've done it so it's within the capabilities of virtually anyone. Hardest thing is to find the wire and all you need to do is look for the one with the orange wrap on it coming out of the bottom of the steering column.
Safety Car
Joined: Aug 2013
Posts: 4,430
Likes: 608
From: Minneapolis Mn
