Windscreen Wipers

[Gollum]

911 SC 1981
Hello - 911 newbie logging in.
I'm getting increasingly frustrated that I can't fix the non-parking problem on my front wipers.
I've read all the relevant posts on here and done the various checks recommended.

The column switch passes the continuity tests on the pins using a multimeter.
I've fitted a new relay under the dash (pig of a job first time to take out the blower motor to get at it)).
This had no effect so took out the wiper motor. Took the cover off and inspected the tracks and contact arms.
These looked all right - nothing broken, plenty of meat on the points of the contact arms and all seem aligned OK- although a lot of grease in there.
Motor spins smoothly enough.
I've also doused everything in electrical contact cleaner (including the fuse box for good measure)

So what else could there be ?

The connections at the wiper motor itself, although I marked them when I toook them off to make sure they went back in the same place, are ripe for nightmare confusion
There are five spade terminals (plus a separate earth terminal) - all the same size !
It would be easy for a PO to have mis-connected one or more wires.
My maths is possibly not up to it but I reckon there is one correct way and 19 wrong ways that the 5 wires can be connected !
ie about a 5% chance of getting it right if you don't know what you are doing !
There are no markings on the terminals that I could see to indicate which wire goes to which terminal.
Can anyone confirm the correct connections or have a pic ?

I still suspect the column switch, but if it passes the continuity checks what else could be the problem.
There is a brown earth wire looped through the wires but not connected to the switch itself- one end connects to the column metal frame underneath but the other end just hangs loose under the dash.
Anyone know where this is supposed to go ? Nothing obvious under my dash.
I've noticed the same wire comes with new switches as advertised on e-bay (for £90 + delivery - gulp!).
I doubt this has anything to do with the wiper problem but I'm running out of ideas.

Help

[Por_sha911]

First of all welcome!
Second, you get double bonus points for doing a search first.
Does your wiper have a delay?
Did you adjust and physically clean the contacts on the column switch (I didn't see where you said anything about adjusting it).
Third, when you get time, we have an informal tradition that we like to see a picture of your ride so we can ooh and ah over your ride.

[86 911 Targa]

Originally Posted by Gollum

911 SC 1981
Hello - 911 newbie logging in.
I'm getting increasingly frustrated that I can't fix the non-parking problem on my front wipers.
I've read all the relevant posts on here and done the various checks recommended.

The column switch passes the continuity tests on the pins using a multimeter.
I've fitted a new relay under the dash (pig of a job first time to take out the blower motor to get at it)).
This had no effect so took out the wiper motor. Took the cover off and inspected the tracks and contact arms.
These looked all right - nothing broken, plenty of meat on the points of the contact arms and all seem aligned OK- although a lot of grease in there.
Motor spins smoothly enough.
I've also doused everything in electrical contact cleaner (including the fuse box for good measure)

So what else could there be ?

The connections at the wiper motor itself, although I marked them when I toook them off to make sure they went back in the same place, are ripe for nightmare confusion
There are five spade terminals (plus a separate earth terminal) - all the same size !
It would be easy for a PO to have mis-connected one or more wires.
My maths is possibly not up to it but I reckon there is one correct way and 19 wrong ways that the 5 wires can be connected !
ie about a 5% chance of getting it right if you don't know what you are doing !
There are no markings on the terminals that I could see to indicate which wire goes to which terminal.
Can anyone confirm the correct connections or have a pic ?

I still suspect the column switch, but if it passes the continuity checks what else could be the problem.
There is a brown earth wire looped through the wires but not connected to the switch itself- one end connects to the column metal frame underneath but the other end just hangs loose under the dash.
Anyone know where this is supposed to go ? Nothing obvious under my dash.
I've noticed the same wire comes with new switches as advertised on e-bay (for £90 + delivery - gulp!).
I doubt this has anything to do with the wiper problem but I'm running out of ideas.

Help

From the factory manual for our '86.

Anything for DR. Wight country............

Hope this helps.

Cheers,

Gerry

[Gollum]

Many thanks folks for the quick responses. Much appreciated.

Joe - I did test the switch contacts prior to and after adjustment. I closed the top contact arm slightly which seemed to have the desired effect on the continuity checks. Did not abrade the contacts at all. They looked clean enough and I sprayed them with contact cleaner.

However, I gave up trying to sort the problem and re-assembled everything thinking that it's not worth spending lots of much money just to sort a parking issue.
It then dawned on me that the continuity tests I did on the pins (as detailed on a post in this forum - thank you Argo ) that the 'off' position I'd been testing for continuity (Pin 4 to Pin 2) was in fact the top position on the arm - which is fast speed. Dumbo !!
Of course the 'off' position is the bottom one on the arm.

So I have top dismantle the switch and go through the procedure again. I still don't have park in the 'off' position and no 2nd speed. The delay knob seems to work on the two speeds I have, although there is a funny noise coming from it and it also doesn't park.

Gerry - thanks for the circuit diagram which is very helpful. Can you advise - is there supposed to be some markings on the multi-part switch on the motor to indicate connections (as on relays) ?
Also any idea where that brown earth wire which comes with the wiper switch is supposed to commect to under the dash ?

I've uploaded some images into Garage as requested but here are a couple for convenience. As you will note I got rid of the tea tray spoiler as a first job. Being a retired accountant I didn't like the 'boy racer' image. Much prefer the 'smooth' look. (OK boys - no nasty comments back !)

[86 911 Targa]

Originally Posted by Gollum

Many thanks folks for the quick responses. Much appreciated.

Joe - I did test the switch contacts prior to and after adjustment. I closed the top contact arm slightly which seemed to have the desired effect on the continuity checks. Did not abrade the contacts at all. They looked clean enough and I sprayed them with contact cleaner.

However, I gave up trying to sort the problem and re-assembled everything thinking that it's not worth spending lots of much money just to sort a parking issue.
It then dawned on me that the continuity tests I did on the pins (as detailed on a post in this forum - thank you Argo ) that the 'off' position I'd been testing for continuity (Pin 4 to Pin 2) was in fact the top position on the arm - which is fast speed. Dumbo !!
Of course the 'off' position is the bottom one on the arm.

So I have top dismantle the switch and go through the procedure again. I still don't have park in the 'off' position and no 2nd speed. The delay knob seems to work on the two speeds I have, although there is a funny noise coming from it and it also doesn't park.

Gerry - thanks for the circuit diagram which is very helpful. Can you advise - is there supposed to be some markings on the multi-part switch on the motor to indicate connections (as on relays) ?
Also any idea where that brown earth wire which comes with the wiper switch is supposed to commect to under the dash ?

I've uploaded some images into Garage as requested but here are a couple for convenience. As you will note I got rid of the tea tray spoiler as a first job. Being a retired accountant I didn't like the 'boy racer' image. Much prefer the 'smooth' look. (OK boys - no nasty comments back !)

The motor should have designated connection points as per the CKT I sent you.

Keep in mind that this a '86 CKT.

Cheers,

Gerry

[James Brown]

Try this Gollum, with the wipers off and the wiper arms somewhere except in the parked position, push the wiper stalk forward (tward the dash) and see if they park.

[Gollum]

Thanks again folks for responses. Much appreciated.
James - I've tried pushing the arm forward. No effect.
In fact took the car out yesterday and it rained so used the wipers a few times (using manual park).
Parked the car whilst shopping and on return - diddly squat from the wipers . The central locking on the passenger door also failed - don't know yet whether there is a common cause (fuse ?).

Haven't had time to investigate further because the Volvo daily ride needs attention for it's MOT, so luxuries like wipers & door locks on the Porsche toy will have to take a back seat for a few days !

[Gollum]

Had another session at this today.
Have definitely confirmed the switch works. Or at least has continuity in 'off' position and all the other positions test OK -per Argo post on here.
Also took out the motor again and checked all the connections on the multi part switch. Re-connected then in line with the Haynes circuit diagram for the 1981 SC (slightly different from the 86 Gerry).
I'm now confident that 1. the dash switch is OK
2. the connections to the motor are OK.
Have to re-connect the motor and test again in situ.

So - had to leave it before testing everything (to catch the Fulham v Man Utd game !)

[Gollum]

Seem to have posted that thread before I intended.

The wiper motor park might seem an easy thing to sort - but it's driving me nuts that I can't pin down the exact fault.

I don't want to go down the bad mechanic route and replace everything - both motor and switch to sort out the problem

Not to mention delay switch and potentiometer - not sure whether they effect things or not.

[Drisump]

"Boy racer" thats good.....but aren't we all just a little bit? I'm afraid that I bought my car partially because of it's lack of a "tea tray". While I was driving it home through northern California a few years ago a friendly guy approached me in a parking lot to talk about the car. One of the first things he said was "too bad it doesn't have a fin". But to encourage me, he said that I could put a "fin" on. I told him that she will remain "finless" because I preferred it that way. He gave me a look of utter astonishment and said to my buddy, who was with me on the trip, "you better have talk with your buddy, I've NEVER ran into ANYBODY who didn't like the fin!" As a result, within a select crowd, the rear spoiler on 911's has become a "fin". Sorry I don't have any input on your wiper problems, good luck and welcome.

[Gollum]

Hello Drisump,
I've a that feeling that Porsche owners probably fall into two distinct groups - the pro-fins and the pro-finless.
Like you - I've met people who say a Porsche should be 'in your face' and the fin is part of the iconic status of the car and shouldn't be tampered with.
You pays your money and takes your choice ....

For those interested I managed to solve this wiper problem.
A PO had wrongly connected the multi point connector at the motor, which I suspected but couldn't pin dopwn without a proper circuit diagram.
There is such towards the end of Haynes - specifically for the 81 SC
This identifies the wire colour coding and terminals to match with the markings on the connector on the motor body.
Works perfectly now so glad I didn't go the 'bad mechanic' route and replace everything willy nilly.
The switch is not always the culprit as most of the posts on here would have you believe.

Pays to think Yorkshire - 'save the brass'

[dshepp806]

Connections are everything............................NEVER assume proper termination integrity and correct connection point(s).

Good find.

Doyle

[Gollum]

Thanks Doyle,
I suppose all this stuff is second nature to engineers, but being an accountant (was !) it don't come easy.

Must say though, the satisfaction after sorting a problem is fantastic.

[Drisump]

Thanks Doyle,
I suppose all this stuff is second nature to engineers, but being an accountant (was !) it don't come easy.

Must say though, the satisfaction after sorting a problem is fantastic.
Doing schematics are just like doing an audit......well almost. Where it differs however is that most audits end in someones tears. Cheers, and happy motoring "sans fin".

[Gollum]

Very true.
The last audit(s) I did had me in tears.
Beiing Canadian, Drisump, Sarbanes-Oxley may not mean much to you.
But our American friends will probably be familiar with those dreadful names.
You can't imagine the torture they inflicted on we poor Brits who worked for American companies and had to implement the total waste of space that Sarbanes Oxley represented.