intermittent wipers

IDrabble · IDrabble's Garage

The intermittent wipers on my '82 SC are not intermittent ie.they wipe constantly when switched on but they do park correctly when switched off.Also when using the windshield washers the wipers will sometimes not park correctly.Obviously these two faults must be related but I dont know how.Can anyone shine some light on the matter for me.

steve rush · 05-26-2002, 11:54 AM

On mine I repalced the small reostat next to guages on dash and my inter wipes worked again. I used a used part at low cost and so never checked to see why old one quit.

Argo · 05-26-2002, 06:50 PM

When I got my '88, the wipers didn't park and the intermittent function didn't work. Thanks to John Walker's Workshop, I found the problem in the stalk switch. In my switch, there are metal contacts (prongs) that activate the park function when they are pushed together by a small angular plastic piece when the wiper switch is turned to off. Over time, they had flexed to the side so that they were no longer pushed into contact by that plastic piece. I repositioned the prongs and, bingo, wipers park correctly. I also found out that the intermittent feature won't work until the wipers are correctly parked. Once I adjusted the prongs, both my problems were solved.

Argo
88 Targa

1bar · 05-27-2002, 05:09 PM

Argo, you're my newest hero.

I've been chasing the same problem with my wipers - they would park "occasionally", and the intermittents would work "occasionally" (read - whenever it was NOT raining!). I just pulled the switch off and found the exact same thing you described. Both sets of contacts that close when the switch moves to the OFF position had bent out of shape and separated, so they never closed.

Now they work great!

Argo · 05-27-2002, 06:01 PM

Glad it worked out, but John Walker deserves most of the credit. I love it - a top mechanic in Washington state gives advice to a New Englander who helps out an Oregonian. On another thread, an Aussie and a Floridian are helping an ex-pat in Hong Kong find someone to install a supercharger. Talk about the brotherhood of Porsche!

Too cool ........

Argo
88 Targa

slider · 01-13-2003, 07:40 AM

Argo -
I'm going to try this also on my 79SC. Pretty frustrating weekend - took apart the fan and duct work near the windshield to check/clean/replace the int wiper relay. No joy. Replaced the int switch on the dash. No joy. By this time, I'm ready to become a manual int switch/park expert myself....

Are the two prongs you mention pretty easy to find? Are they more easily identifiable by placing the switch in one of the other upper positions?

Many thanks in advance. 1bar - any help from your experience would be welcomed too!

thanks all.

1bar · 01-13-2003, 07:50 AM

Slider -
The wiper switch is a little confusing. Pull the steering wheel off, then the plastic shroud around the column. Then remove the switch so you can hold it in your hands and play with it. I think Wayne's 101 book shows the process?

Anyway, I had to move teh switch back and forth, watching how it works inside, quite a few times before I figured out how it works. It's not that complex, it was just a little different than I was expecting. The repair takes about 30 sedconds once you see the problem.

You COULD buy a new switch - Pelican has them. If you have trouble, there's always a backup. But mine is still working after 8 months - and even in the rain!

Larry

masraum · 01-13-2003, 08:01 AM

1bar, out-freakin-standing, same problem as with the highbeams basically. I also have the park works intermittently when really wet/damp, and intermittent wipers don't work when really damp. Glad I never spent money on a new switch or rheostat.

Argo · 01-13-2003, 11:01 AM

Just ran across your post. Like 1bar says, remove the wheel and clamshells and the 2 screws holding the switch so you can take a close look at it and it will be pretty clear how it works. While searching for a picture I remember being posted some time ago (sadly, in vain) I ran across this post describing a way to test without removing everything:

This was indeed the same problem that I had AND my intermittent relay was shot. The easy way to test the steering column switch is to remove the six pin plug (connector) that plugs into the body, which goes into the luggage compartment. You should be able to spot the wires coming from the steering column and keep following them, until you get to where the wires go through the body. Hopefully this will hold true for a 77 as well.

If you unplug this and you have a multimeter (continuity tester) handy you should be able to test from this point.

Turn the connector until the notch is at the top and call this pin number one and then count clockwise to pin number 6.

This is the way it should be.
Off position - Pin 4 connects (shorts) to pin 2
1st position - Pin 4 shorts to pin 1
2nd position - Pin 1 shorts to pin 3
3rd position - Pin 1 shorts to pin 6
Wash position (pulling back on stalk) - Pin 1 shorts to pin 5.

If the problem is in the switch you will see that Pin 4 does not short to pin 2 i.e. open circuit while the switch is in the off position. That connection is there to supply 12V to the windscreen wiper motor permanently, the motor then continues to turn until it reaches the park position where a break in the circuit within the windscreen wiper motor will automatically cause it to switch off.

Personally, I prefer removing stuff and watching it function. Either way, I'd look at this switch for the problem; they seem to be the source of trouble more frequently than the relay or wiring.

Argo
88 Targa

slider · 01-13-2003, 12:19 PM

Perfect - Thanks 1bar and Argo. I'll take a look at this tonight and let you know how it turns out.

I have the same kind of nagging problem with the side-view mirror switch. Replacing the switch didn't help. Any thoughts?

Joe

Argo · 01-13-2003, 08:52 PM

RE: the side view mirror switch - which switch did you replace? The mirror adjuster switch on the driver's door or the mirror selector switch (driver or passenger mirror) on the dash?

Argo
88 Targa

slider · 01-14-2003, 04:06 PM

sorry for the lack of clarity - the mirror adj switch on the drivers door.

My son's 13th birthday was last night - and felt I needed to review my priorities, so I did birthday fun instead of p car repairs.....I think I made the right choice, but no update on the int switch.

Argo · 01-14-2003, 08:46 PM

You did the right thing. When you get a chance, try toggling the dash switch to the other side and see if the problem is still there. If so - and it's just a long shot - check the wiring where it leaves the driver door and enters the body. My door rubbed against this bundle when I closed it and it eventually wore through the insulation leaving bare wire prime for a short. If it's not one of these things, it's multimeter time .....

edit: this is all based on an 88; yours may be different.

Argo
88 Targa

car911 · 01-14-2003, 10:41 PM

Someone (I believe it was in another thread but still related to intermittent wipers) suggested faulty grounds triggering erratic electrical behaviour, especially in damp weather. So, I took a few minutes to spray contact cleaner on all electrical contacts that I could see on the fuse block and in the trunk area. And jiggled all the connections.

Lo and behold, my annoying intermittent wiper behaviour stopped (at least for now)! Assuming this at least narrowed down the problem, the principle of trying simple things first makes a lot of sense.

Consider that these are low voltage connections which are 15-20 years old in basically a harsh exterior environment. A routine cleaning like this is a obvious first step.

car911 · 01-14-2003, 10:43 PM

I asked this question before but got no answer. In my 84 Targa, in the front of the trunk right next to the washer pump is what appears to be a relay. Removing it does not affect the wipers, washers or headlights. It is clearly original equipment. Anyone know what this is?

k9handler · 01-15-2003, 12:27 AM

Argo is the man! I have had the same issue...just never thought to actually look into why it did this. Now I must go and fix it. Thanks for the info, this BBS is the best!

k9handler · 01-15-2003, 01:00 AM

well...it's kind of fixed.

I was not able to get the lower section of the column off...but was able to reach in and push and prod with my fingers, and the wipers now work as designed. Thanks.

But for future reference...other than the screw on each side, what is holding th lower column section in place?

1bar · 01-15-2003, 06:03 AM

k9 - I recall that the screws at the front end of the column, one on each side, had to be removed as well to get the clam shell parts off. Don't think I have a picture.

Larry

Argo · 01-15-2003, 07:26 AM

What 1bar says - IIRC, you have to pull the steering wheel to access those screws. Once the clamshell is off, the rest is easy.

Argo
88 Targa

CrossT · 01-15-2003, 02:02 PM

Somewhat and overall similar irregularities on my 86. I pulled the wheel, the upper/lower clamshels and cleaned out the wiper switch (carefully) with small brush first and then a piece of very fine snadpaper folded in half to run in between the contacts in the switch, cleaned and blew out the resulting dust. Functions perfectly now.

todd
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86 cpe