Insane wipers = NLA windshield wiper switch?

[Jerome74911S]

There have been a number of threads about windshield wipers that suddenly turn themselves on, and then cannot be turned off. That's what I've got.

Here's what I've done:

1. Found damaged ground wire and patched this.

2. Cleaned ground contact and reassembled everything.

3. Result = Wipers no longer worked at all - no uncontrollable running, no normal running.

4. Took the whole business apart again and further cleaned contacts, reassembled.

5. Result = Wipers running and won't shut off, same as before.

So, what should I do next to analyze? These switches for '74-'75 are NLA. Some pictures:

Melted and abraded ground wire.


Fixed ground wire.

[Jrboulder]

dC AutomotiveOver 140,000 square feet of new and used Porsche parts

[Jerome74911S]

Originally Posted by Jrboulder

dC AutomotiveOver 140,000 square feet of new and used Porsche parts

Yes, I found one at dC for $50. However, their minimum order is $75 and I don't need any other used parts at the moment. Do they guarantee parts?

But, I don't care to replace parts as a diagnostic method. How do I go about testing the switch?

[cabmandone]

Originally Posted by Jerome74911S

Yes, I found one at dC for $50. However, their minimum order is $75 and I don't need any other used parts at the moment. Do they guarantee parts?

But, I don't care to replace parts as a diagnostic method. How do I go about testing the switch?

Send me a pic of your switch. I've got one from my 75 donor I'd sell you for 50 shipped. I just want to be sure it matches yours.

OOPS! you're in Quebec, I'll need to see how much shipping is. Sorry. Let me know if you're interested.

BTW, isn't there a wiper relay up front in the trunk area?

[Jerome74911S]

Originally Posted by cabmando

Send me a pic of your switch. I've got one from my 75 donor I'd sell you for 50 shipped. I just want to be sure it matches yours.

OOPS! you're in Quebec, I'll need to see how much shipping is. Sorry. Let me know if you're interested.

BTW, isn't there a wiper relay up front in the trunk area?

Tell me if this is a good enough picture. Part # on it is: 911 613 306 01, this is printed on the front. BTW, it could be shipped to a Vermont address if this works out.

I'd still like to test my existing switch, though. I don't know about a relay in the trunk - where is it?

[Tidybuoy]

Keep checking the classified. I recently bought a new switch for my '74 for $50 and it worked perfect. I had issues with my old wiper switch, the wipers turned on every time I went over a bump.

[Tidybuoy]

Originally Posted by Jerome74911S

Jerome,

I have a '74 and I'm assuming you do to. I noticed that in your photo, you don't have the intermittent switch that is usually on the dash (your photo has a plug).

I'm wondering if you don't have the intermittent knob, then maybe someone has made adjustments to your car and that could be contributing to your issues??

[Jerome74911S]

Originally Posted by Tidybuoy

Keep checking the classified. I recently bought a new switch for my '74 for $50 and it worked perfect. I had issues with my old wiper switch, the wipers turned on every time I went over a bump.

Thank you. I'll do that. Lucky you.

[Jerome74911S]

Originally Posted by Tidybuoy

Jerome,

I have a '74 and I'm assuming you do to. I noticed that in your photo, you don't have the intermittent switch that is usually on the dash (your photo has a plug).

I'm wondering if you don't have the intermittent knob, then maybe someone has made adjustments to your car and that could be contributing to your issues??

I wondered about this, too, but I have had the car for almost five years now without any issues with the wiper switch. I can't see where alterations might have been made, but this doesn't mean there weren't any. Of course, the plug has 'always' been there on the dash. Did every '74 have intermittent wipers? The part number on the switch is correct for this car. Another mystery; that's a relief. I thought this car had stopped providing mysteries.

[cabmandone]

I thought the knob above the plug was the intermittent. What is it if it's not the intermittent wiper? BTW, I can do $50 shipped to Vermont. I'll get you a pic of it tomorrow. If it doesn't work, put it in a flat rate box and send it back, I'll refund all but the shipping out. $10 for a test switch might be money well spent.

[Jerome74911S]

Originally Posted by cabmando

I thought the knob above the plug was the intermittent. What is it if it's not the intermittent wiper? BTW, I can do $50 shipped to Vermont. I'll get you a pic of it tomorrow. If it doesn't work, put it in a flat rate box and send it back, I'll refund all but the shipping out. $10 for a test switch might be money well spent.

The knob you ask about is the odometer reset. It's a dismal thing to use, since it is very stiff to turn - it connects to the end of a longish flexible cable that goes into the speedo.

So the switch you have has the same part number as mentioned by me above? If so, PM me and let's work something out.

[Tidybuoy]

Originally Posted by Jerome74911S

I can't see where alterations might have been made, but this doesn't mean there weren't any. Of course, the plug has 'always' been there on the dash. Did every '74 have intermittent wipers?

I don't know if all cars had this intermittent switch on the dash but I can say that my 914 has the same switch. I can't imagine Porsche putting this on the 914 and not on the 911 - but who knows.

Here's a quick photo of my dash knob. Also check your owners manual as it usually states "optional items". I was going to look at mine but I seem to have misplaced the manual.

[javadog]

Intermittent wipers were originally an option and the switch was located on the dash face, to the left of the ventilation controls. Porsche moved it up higher, to the instrment cluster, later.

JR