Electrics help needed

[Dlc]

E9 Friend,
I have been doing some odds and ends to get the car ready for the annual cruise thru the Alps - due to start in one week.

I am stuck with two separate phenomena:

1-the washer pump does not engage. I have tested it separately and it works. When I pull the wiper stalk on my '71 CS the wipers go off as they should, but no water spray. Any inspiration would be greatly appreciated.

2-the horn button causes the wiper to go off (as it would when you activate the washer function), but no horn. I separately tested the horn from the relay onwards and it works, so the gremlin must sit within the cabin. Again - any inspiration would be greatly appreciated.

thank you!

Dominik

 

[Arde]

E9 Friend,
I have been doing some odds and ends to get the car ready for the annual cruise thru the Alps - due to start in one week.

I am stuck with two separate phenomena:

1-the washer pump does not engage. I have tested it separately and it works. When I pull the wiper stalk on my '71 CS the wipers go off as they should, but no water spray. Any inspiration would be greatly appreciated.

2-the horn button causes the wiper to go off (as it would when you activate the washer function), but no horn. I separately tested the horn from the relay onwards and it works, so the gremlin must sit within the cabin. Again - any inspiration would be greatly appreciated.

thank you!

Dominik

Hi Dominik,
1- For the washer pump I suggest you try one terminal at a time, namely, keep the positive on the battery (contact 43 of motor 25 in the diagram) and use the switch to provide the negative as in the normal wiring (contact 42). If that works then switch 50 provide the ground correctly, else you know that is the problem. Next keep the battery negative to contact 42 and run contact 43 through the switch 50 and relay 53. If if does not work then the switch or relay are bad.

2- use the horn to activate the wiper .

https://e9coupe.com/tech/autobooks/autobooks_manual.pdf

 

[ScottAndrews]

Did you by any chance open up the column and do anything to the wires? Sounds like the horn wire is somehow shorting to the wiper wiring. Things are pretty tight up inthe head of the steering column, so it is possible there is a broken washer wire and a shorted horn wire.

 

[Dlc]

Did you by any chance open up the column and do anything to the wires? Sounds like the horn wire is somehow shorting to the wiper wiring. Things are pretty tight up inthe head of the steering column, so it is possible there is a broken washer wire and a shorted horn wire.

I had opened up the column to swap the wiper/blinker switch. Yesterday I tested the wiring from switch to plug to firewall to horn relais and this works.
I also tried a different wiper stalk switch. No change, still the wiper is activated in washer mode when the horn button connects to ground.
Per the wiring diagram both the horns and the wiper motor are connected to fuse #6, so there must be a short somewhere.

 

[Arde]

Try grounding pin 85 of horn relay 21 and see if the horn works. If it does then the wring to the horn button is wrong.