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> Bad relay board?
saigon71
post Sep 9 2013, 05:37 PM
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Running a stock 2.0 D-jet.

Got some crazy electrical issues going on...need to get everything fixed before inspection. My reverse lights aren't working. Verified that the switch itself is working properly by checking continuity of the switch with the car in and out of reverse. I have continuity from the reverse light switch to the relay board.

Here's where it gets weird. With the car in reverse, I turned the ignition on but didn't start the car. The fuel pump operated normally, stopped buzzing in a few seconds. When I turn the lights or turn signals on with the car in reverse, the fuel pump runs constantly. If I take the car out of reverse, the fuel pump stops running.

I tested all the relays on the control board by swapping them out with one on the headlights.

The reason I suspect the control board is that it is the common link between the back up light switch and the fuel pump.

Anyone encounter anything like this?
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914Sixer
post Sep 9 2013, 09:15 PM
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Reverse light switch has a little pin behind it that wears way over time. It has to push the plunger in the switch. This may be the reverse light problem.

Not sure about the other stuff. The fuel pump relay on board also operates the wire on the lever to turn on heater blower motor. If the wire to the lever has a problem it will cause fuel pump issu

Relay boards are pretty reliable all the way around. They got a bad rap along with the ECU's from poeple that did not understand the operation.
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saigon71
post Sep 10 2013, 06:50 PM
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Wanted to follow up on this thread in case anyone else runs into similar problems:

Picked up a good used relay board from Aircooled Racing this morning...I was glad they had one laying around they were willing to part with. Cleaned it up and installed it. My fuel pump no longer runs constantly when I put the car in reverse with the engine off. biggrin.gif
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ConeDodger
post Sep 10 2013, 07:01 PM
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Generally I'd say the relay board is the last place you look for a problem but this is what happened to me...

Went down to Santa Rosa for a Zone weekend. Two nights in a niceish hotel in Santa Rosa... Gonna be fun right? Car drove like a top all the way down. Stopped by the OC on the way and McMark made adjustments... I don't recall every symptom but it was crazy electrical stuff. Mark put an optical ignition module in that he had laying in a box. Ran much better. We thought we were golden. Off to my hotel I went. In the morning, I took off for Charles Schultz and the autocross. Car killed on the on ramp. Towing company hauled it to the OC and McMark meets me again on his day off to sort it out. Finally, after trying a few things, he pulls out the relay board. Tar is intact but if you look in the little cracks, bright green moldish shizzit... Mark plugs in a spare and off I go. No more electrical problem.
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saigon71
post Sep 10 2013, 07:07 PM
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QUOTE(ConeDodger @ Sep 10 2013, 09:01 PM) *

Generally I'd say the relay board is the last place you look for a problem but this is what happened to me...

Went down to Santa Rosa for a Zone weekend. Two nights in a niceish hotel in Santa Rosa... Gonna be fun right? Car drove like a top all the way down. Stopped by the OC on the way and McMark made adjustments... I don't recall every symptom but it was crazy electrical stuff. Mark put an optical ignition module in that he had laying in a box. Ran much better. We thought we were golden. Off to my hotel I went. In the morning, I took off for Charles Schultz and the autocross. Car killed on the on ramp. Towing company hauled it to the OC and McMark meets me again on his day off to sort it out. Finally, after trying a few things, he pulls out the relay board. Tar is intact but if you look in the little cracks, bright green moldish shizzit... Mark plugs in a spare and off I go. No more electrical problem.



The only reason I suspected the relay board is because it was a common point for the reverse light circuit and fuel pump. I agree, the symptoms are crazy! I need to add one of these to my spare parts road kit!



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saigon71
post Sep 10 2013, 07:10 PM
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Any 914world.com members rebuilding these things? Saw the price for a rebuilt one from an old AA catalog today. (IMG:style_emoticons/default/barf.gif)
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Mike Bellis
post Sep 10 2013, 07:57 PM
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QUOTE(saigon71 @ Sep 10 2013, 06:10 PM) *

Any 914world.com members rebuilding these things? Saw the price for a rebuilt one from an old AA catalog today. (IMG:style_emoticons/default/barf.gif)

I have been thinking about rebuilding these. I'm sure the AA price could be cut in half.
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