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1981 Fuse board fuel pump relay and bypass

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could the factory recall have housed the bypass relay in the engine bay?

I have a 1981 MK1 cab just imported from the US. It won't start! In the board it appears to be missing a fuel pump relay. I have puchsed this and put it in position L - pump still does not fire up. There appears to be a fuel pump bypass relay in the engine bay. Is there another relay missing above position L?

Thank you
engine bay relay.jpg
fuse board 2.jpg

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Actually the Fuel PUMP relay was a TSB that took the original position in the fuse panel, and moved it to an auxilliary position above the fuse panel in one of the "add on" locations then ran a jumper wire from the original socket to the add-on location.

POS (Previous Owners Syndrome) can locate anything anywhere, and you start to Curse those that did that including wire nut repair of wiring faults, or not isolating burned wires

Cabby-info.com has some good information on this under the Electrical section.

IMPORTANT NOTES:

Fuse amperage: Green = 30; Yellow = 20; Blue = 15; Red = 10.
1980-1982 Cabriolets use ceramic fuses; their amperage is listed on the diagram.  
1980-1982 fuel pump relay: Originally installed in position L; due to a recall, the relay should have been moved to position 1 with a wiring loom bridge to position L.
If your car has factory-installed heated seats, the relays for this option are under each front seat.
If your car has a factory-installed 2-stage after-run cooling fan system ('88+), the relay for this fan is mounted to the left front fender.
If your car has factory-installed power windows, there is a control unit beneath the dash on the passenger side.
If your car has a factory-installed power top, there is a covered thermo-fuse above the relay panel.
If your car has factory- or dealer-installed daytime running lights, there is most likely a relay attached to the top of the panel (not shown in the diagrams).
ALL 1983-1993 Cabriolets are CE1

Screen Shot 2019-05-10 at 9.50.41 AM.png

So you are on a voyage of Self Discovery, but know that the relay in question should only operate if the key is in the start position…



What do Divorces, Great Coffee, and Car Electrics all have in common?

They all start with GOOD Grounds.

Where are my DIY Links?

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Thank you Biano1234 - been all over the mapping at Cabby Info. everywhere I look online there seems to be a bypass fix (following a recall) and yes everyone seems to refernce the Cabbyinfo picture. However, is it possible the relay in the engine compartment is the bypass relay rather than be in the fuse box? When I test position L with a power test I'm getting power. So when they did the bypass would they still have left a live feed when they repositioned the relay following the recall?
Head scratching stuff. Picture of the old girl in question FYI lhd1.jpg

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Anything is possible.  Remember the POS can also be referred to as Previous Owners Servicing or POSER Previous Owners Stupefying Equipment Repair.

That could be where they relocated the relay Wigging the wires out with a DVOM as they used the same color wires (STUPID STUPID STUPID) I suppose because buying different color wires wasn't in their plans..or labeling them…  is going to tell you more than I can, as they should all go back to the original positions on the Fuse Panel eventually.

That doesn't look like the atypical fuel pump relay that I am used to seeing on a Cabriolet, I am more used to CIS or Digifant, which are totally different, where as the Digifant is more like the standards 40A horn relay.


What do Divorces, Great Coffee, and Car Electrics all have in common?

They all start with GOOD Grounds.

Where are my DIY Links?

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Hi Briano

Thank you again. The car is 100% original and untouched. Any re-wiring will have been done on the recall. It is strange that there is still power to position L - but if you look at the surface of L it looks like there has not been a relay in the slot for years - but the one above looks like it had a relay. However, the mapping of the pins above mean the fuel pump relay does not connect to the connectors behind. I had hoped to solve the problem myself but I think the time has come to pay and call in a MK1 electrical expert. I also want to get the cambelt changed and the Air Con going (no history with the car but the 78k on the clock all looks genuine from the car's condition) I'm in Worthing West Sussex - are you aware of any good mechanics who know these cars like the back of their hands in the area? Regards Chris
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