90-93 Automatic Transmission intermittant NO Start Fix

Have you done so much to the car today that it just doesn't fit into one section, or are you too damn lazy to split it all up? Either way, this is the section for you.

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Briano1234
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90-93 Automatic Transmission intermittant NO Start Fix

Post by Briano1234 »

I have started a new topic as the fix is specific to 1990-93 cabby's with automatics and may apply to other VW products too.

I had a intermittent no start condition on my cabby, I had already installed the hot soak fix for the auto, but the damn thing would intermittently refuse to start when cold, warm, or hot. I replaced the hot start relay, the starter, and finally the ignition switch which is a major pain in the ass but nothing resolved the issue.

Going over and over the Bentley I found the starter interlock relay might be the cause, and I would be damned if I could find it.

According to the Bentley, it was to be in position 15 on the fuse panel, and according to the ETKA it is to be in position 14. Well 15 is devoid of relay, and 14 goes to my radiator fan... so where in the hell is that relay.

I did find that the relay marked 92 p/n 191 927 181 is only on 90 and up Digifants with Automatic trannys and it is on the back side of the knee bar kinda hidden who would of thunk.

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After finding this relay it finally went out completely....well half of it did.

To see how this relay works differently from the normal starter you have to turn to the Shift lock mechanism diagrams for the wiring in the Bentley.

There you get to see the relay, the Bentley main diagrams don't refer to a different section for automatics.. A foot note would of been great, as well as the correct position.........

From the Start switch 1/2 of the relay is powering the ECU. That pick part of that solenoid energizes the other half of the relay that when all the other interlocks are met (ie: the car in park, brake depressed....) you throw the key switch to the start, it energize and engages the starter, so if that half of the relay goes bad you can't start your car, but if you jump the starter it will start. It doesn't matter if you have the hot start fix as on the 90-93 cabby it uses the relay to engage the starter solenoid (or the hot fix solenoid).

Here is the fix as I had half a flaky relay. it was intermittent, then went out I opened the relay and only saw the ECU side pick the other side for the starter didn't pick at all.

From the Ignition switch harness find the red/black wire coming out of the switch and cut it long away from the harness

From the relay that is under the knee bar find the red and black wire and cut it.

Un-wind the red/black wire on the relay marked 92 (it is the only large red/black wire on it ) from the loom then route it over the steering column and splice it in to the red and black wire that goes back to the switch. This is only energized at the start switch position, and will allow the Key to then engage the hot start relay, and start your car.

Since you didn't bother the Digifart side of the relay it will run the car.

This only applies to Automatics 90-93, and you will have by-passed all the bs interlocks... So remember you can start the car in any gear.. so park it... or neutral it....

At J E Vw the relay was 72.00, not in stock. BOO JE
At DH the relay was 59.00 not in stock. Why the difference in price?


After about 8 hours replacing things and ripping apart the Dash and the Knee bar I have the fix for you.
Brian's fix 2 cuts and one yellow in-line splice...........
You can do this fix in about 10 minutes under the dash now that you know what to look for and where the parts are located.

Adding The schematic fix.

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Briano

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