Wipers Won't Turn Off

[chris belyea]

So I'm hoping to get some opinions here. I was doing some electrical testing on the windshield washer pump. While doing so, I believe I might have fried my wiper relay. When I turn on the ignition, the wipers won't turn off. They do change speeds. No intermittent or off. So do you think it's the relay or could it be something else? Also, When I look up the part number for the relay, it appears that they or no longer made. Anyone have a source?

Thanks

Chris

[Scott A]

since the power has to first go thru the lever at the steering wheel...then that lever/switch is probably the problem.

electricity flows like water..... in one direction....#1. from battery, to #2, key switch, to #3, the lever at the wheel, then lastly to #4, the wiper motor itself.

it could really only get power after it has gone thru #3. (it feels like your #3 is constantly in contact)

(temporary, you could pull the wiper fuse) just to get it to stop. you'll have to remove the steering wheel to get at that switch.

the lever at the wheel is a fragile little guy that does a lot of work, in a lot of directions....and you probably helped it knock something out of place...as you were pulling to see if the pump would go.

[tom1394racing]

Chris

If this is for your '70 project, you have a unique wiper system that was used only for the '70 model year. This system uses two unique relays to control the wiper system as well as a one year only wiper motor. The attached photo is from my '70E project prior to disassembly.

[tom1394racing]

Here is some added info

http://forums.pelicanparts.com/porsc...per-relay.html

http://forums.pelicanparts.com/porsc...-question.html

[chris belyea]

Thank all. The more I think about it, I'm starting to think it might be the switch since the wipers won't shut off. I need to disassemble a few things and try problem shooting.

Chris

[chris belyea]

So...an update. I disconnected the 6-prong connector at the fire wall from the steering column wiper assembly. Powered the ignition back on and the wipers still run. Since the wiper switch is disconnected and the wipers still run, wouldn't that point to the relay?

Chris

[Scott A]

It does sound like a relay that is stuck closed. Unplug the relay, if two, one at a time. And if the wipers stop...then maybe that relay has melted shut.


Is there a chance you unplugged a positive wire and plugged it back into the wrong receptor?

Relays don't make power, they are just an open/close switch...activated by a switch you pull.

But the relay can't get power until you pull that switch. So another failure point is still the switch at the wheel. A 12v test light will tell you if power is making it through a switch, or always stuck on.

By the way, if you find it is a relay, you can pry it open and fix the part that is stuck, without having to buy a new one.

[chris belyea]

Scott,

So I didn't unplug any wires and they were working correctly before I worked on the windshield washer pump, so there's no chance that a wire is connected incorrectly. Based on the wiring diagram, there is a hot wire that goes directly from the fuse box to the wiper motor and then to the "Follow-Up Switch" relay.

I've now tried the following and here is the result:

With the wiper switch unplugged:

Unplugged the " Follow-Up Switch" relay and wipers don't run.
Unplugged the " Interval Switch" relay and wipers run.
Unplugged both relays and wipers don't run.

Then I plugged the wiper switch in and tried the following:

Unplugged the " Follow-Up Switch" relay and wipers stop. When I turn the switch on, the wipers turn on and off but don't park.
Unplugged the " Interval Switch" relay and wipers run.
Unplugged both relays and wipers stop. When I turn the switch on, the wipers turn on and off but don't park.

So it's pointing to a relay in my opinion. Do would you start with the "Follow-up Switch" relay and open it up and see? That's the only relay receiving power (switch on by the ignition) from the fuse box.

Chris

[Scott A]

I would open that relay, just go slow, and careful, don't break the little wires..
you will probably see the contacts are fused together. just work them apart....and file the contacts back to smooth..
i bench test the relay with 12v....and watch it work.

wipers have 4 wires going into them...and i think 2 of the 4 help it park...that will probably work fine. once the relay is fixed. (maybe one relay is just for parking)

i am no expert at this.....i just do it every day, for about the last 40 yrs.....i guess as a hobby.

[chris belyea]

So I've opened both relays and I don't see anything noticeable. It appears that there are contacts touching, but they are not fused. Both relays appear to be this way so I'm assuming it was normal. I see some discoloration on the top of the contact plate.