Windshield Wiper Issue

[Bulldog9]

I've been trying to track down a problem with my windshield wiper motor. I've read several threads on the issue and before I tear into the motor, want to confirm that the contacts in the motor are the issue.

The issue is that the wipers do not park and the intermittent setting does not work. Here is what I have checked/confirmed so far.

1. The Switch is fine, contacts are not sticking, but the wipers stop wherever the switch goes to off. The wash and low/high speeds work fine but wipers don't 'park.'
2. When I turn the knob for the intermittent wipers the relay clicks intermittently as it should, but the motor does not turn. So this makes me think the relay and switch are fine and the problem is in the motor itself
3. Occasionally, the wiper motor squeels when turned on.

I think all this means it is the grounding contact in the motor that tells it to park, but I have NO experience with it.

I've only found one thread on the subject and the pics/instructions were not clear enough for me to feel confident tearing into it. Despite my best effort, I really stink at the 'search' thing. ANyone have a detailed 'how to' rebuild the wiper motor, specifically the contacts for park and such? Thanks!

[gomezoneill]

Sounds like your motor is fine because it works normally except when parking. I believe there should be power to the motor to park.Check your fuses first and give them a close look and a little spin to make sure they have a good connection. If this doesn't work replace the intermittent wiper relay.

[dfhtrhjn]

One of my 911s has exactly this behavior, and I still haven't had time to find the problem. I replaced the intermittent wiper relay which is behind the wiper motor accessible from the trunk which didn't help.

I was contemplating ordering a new Potentiometer (Intermittent Wiper switch) but I haven't made the leap yet.

Does anyone know what fuses to check for the wiper system?

[dfhtrhjn]

I also read that the park feature of the wiper system is in the motor. This is the case in many cars, including my Land Rover which had the same issue, and was resolved when I replaced the motor.

I'm not sure what to replace first.

[Targalid]

Definitely you need to solve this problem. Then you can explain it to me. I have exactly the same behavior from my wipers and haven't yet found the answer. I use the wiper switch to park my wipers on the passenger side. I like this feature but it isn't really a feature is it?

[dfhtrhjn]

Haha, I do the same thing. When I get it working I'll be swapping the park side. My wiper switch is really loose, worn out, and sloppy. I had planned on taking it out and repairing it like I did with the lights, but I may start with a new switch instead to save time.

[Bulldog9]

Will definitely report back. I don't think it is the switch, potentiometer or relay. I pulled the relay out, opened it up. cleaned all the contacts, used electronic parts cleaner, etc. When I plugged it back in, I turned the pot and the relay clicked on and off in variable sync with the potentiometer.

I am going to pull the air box out and pull the motor this weekend. Want to finish before I put in the carpet etc in the trunk.

[dfhtrhjn]

Oh interesting. If my new relay isn't clicking, could it be the potentiometer? I haven't tried to listening to it yet.

[Mark Salvetti]

I think it is the wiper switch. Try gently pushing the switch up. Mine would turn the wipers off, but it did not engage a little reed switch to park the wipers and allow the intermittent wipers to work unless I forced it a little bit. The fix was to open the switch and glue an extra piece of plastic in position to close the reed switch when in the off position.

Mark

[pete3799]

My no parking problem, after checking the relay (OK),and pulling the wiper motor (OK) turned out to be in the wiper stalk. After pulling the switch out and checking it on the bench it all appeared to be working fine. The contacts all seamed to be making, however when checking the breaker contacts with and ohm meter I found one that wasn't completing the circuit.
If I remember correctly it was contact that's connected to the blue wire in this picture. Cleaned it up and tweaked it a little and it's been fine since.

[dfhtrhjn]

Looks like I've found new motivation to tackle this problem.

[flat6_911]

I had the same issue and replaced the stalk. Fixed the issue.


Sent from my iPhone using Tapatalk

[steely]

I tend to agree with you that it could be the motor cam reed switch contacts related to the motor cam itself, based on your description of items 1 &2, and my limited experience with my rear wiper on my ‘87 – but I’m a little confused given so many guys said they solved a similar issue by replacing their stalk switch. My understanding was that as long as the wiper motor started working (assumes stalk & relay worked and power got to the motor), then the parking power would bring her home. The parking power is unswitched and should be present at the motor no matter what position the stalk switch is in, b/c it is not routed thru the stalk. It was the action of the wiper motor and its cam driven switch that removes parking power to the motor at the motor itself. The reed switches in the stalk and motor do act up however when they get old, so ymmv and hence the stalk solution. I’d recommend carefully checking for unswitched power on the applicable motor terminal but I don’t have a schematic for that year.

edit: hopefully this is a better help / correct vintage/ looks like the path could be thru the switch too: http://forums.pelicanparts.com/porsche-911-technical-forum/605809-mystery-electrical-component-wires-74-911-a.html

[dfhtrhjn]

Ok I go it working, my problem was in the switch.

The plastic bar currently below the metal leads connects them when in the off position activating the park in the wiper motor.


The two leads in the center of the picture need to be touching when the stalk is in the off position, but not in any other position or it will cook the fuse.

In the off position I pushed on the lead with a screwdriver to verify the solution. Then I bent the outer metal lead about 1/2mm closer so that the fatigued plastic bar will connect them.


The park feature and the intermittent wiper started working once the wiper park circuit was connected.

I'm experiencing intermittent service from the intermittent wiper. I had to wiggle the potentiometer quite a bit since it hasn't run in 14 years, even though I have a fresh relay. I'll probably have to clean the components thoroughly and maybe replace the potentiometer before it works every time, but at least the wipers park.

It took me about 15 min the get down to the switch, and about another 30 min to correct the issue and put it back together. For those who also experience these symptoms, I highly recommend checking the switch first since it's pretty easy.

[markwatson]

how do i position wiper arm

[markwatson]

wiper arm on 996

[rubing]

I've been having this same issue with wipers not going into park on my 1977 911. I'm having a bit of trouble getting access to the stalk itself. i removed two small phillips screws on both sides of the black plastic piece which surronds the stalk (one is on turn signal side and one on wiper switch side). but that black piece of plastic is not removable once the screws are out. I tried jiggling it and it won't budge...don't want to force it and break something. is there another screw here or something holding it in that i am missing? thanks

[pete3799]

Originally Posted by rubing

I've been having this same issue with wipers not going into park on my 1977 911. I'm having a bit of trouble getting access to the stalk itself. i removed two small phillips screws on both sides of the black plastic piece which surronds the stalk (one is on turn signal side and one on wiper switch side). but that black piece of plastic is not removable once the screws are out. I tried jiggling it and it won't budge...don't want to force it and break something. is there another screw here or something holding it in that i am missing? thanks

Steering wheel has to come off then you'll see the other screws that need to be removed.

[dap930]

You can not remove the plastic collars without removing the steering wheel. Once removed there will be two more screws plus two screws that hold the horn contact strip. When all that is removed the wiper stalk can be removed by removing two mounting screws. You can check the "park" contacts in the switch by pushing the stalk arm towards the front of the car. If the wipers park, then the "park" contact that is "made" when the stalk is in the off position needs slight tweak. My wipers were intermittently parking particularly after using the washers when I discovered if I pushed the stalk forward the wipers would park. I cleaned the contacts with contact cleaner, but the contact needed a slight tweak to close the contacts properly. You can adjust the contact leaf with a jewelers screw driver, just don't over do it.

[Halvo]

My symptoms: wipers won't park / return to "home" position and the intermittent wiper switch doesn't work (I can hear some clicking but nothing happens). HOWEVER - when I push the wiper stalk toward the dash, everything works fine. THIS IS A CONTACT PROBLEM WITHIN THE SWITCH.

The fix was exactly as described above with the excellent photos posted.

For my Momo Prototipo: Remove horn cap, disconnect. 29mm deep socket to remove steering wheel nut. Good tug on steering wheel to remove it.

Remove the two large screws holding the horn contact in place. Let it dangle.

Remove the 4 small screws holding the black plastic shroud in place, but there are also 2 small screws on each side, so total of 6 screws to remove the black plastic shroud.

Remove the 2 small screws holding the cruise and wiper switches to the column.

Pull the cruise switch out of the way and let it dangle.

Push the wiper switch toward the dash and it will free up so you can have a look.

There are two thin metal tabs that make contact when the switch is in off position by a white piece of plastic pushing them together. With time the plastic wears down and/or the metal tabs bend toward the driver, so they no longer make contact unless you push the stalk toward the dash/frunk.

Put the switch into high position (with car off), and very carefully bend both metal tabs away from the driver, toward the frunk. But don't push so much that they make constant contact. Make sure there's about 1mm between them.

You can now test it without putting everything back together. Just turn key until dash lights come on, and test the wipers (with arms pulled away from glass of course). Once you have it adjusted correctly, the wipers will "park" and the intermittent wiper function should work. I also sprayed some Deoxit on all the metal contacts within the switch, as my medium speed wasn't coming on without some fiddling.

Now everything works perfectly! THANK YOU!! This forum is awesome. If you also have issues with your high beams coming on over bumps, this is also due to contacts that have bent over time. Search for that thread - the contacts are on the left hand side and you don't even need to unscrew/remove the switch. Just bend the top of the thick silver metal bar toward the frunk by holding it firmly in the middle with pliers and then using needle nose pliers to bend the top toward the frunk. Worked perfectly!