Lazy wipers + wiring diagrams

[Guest]

My wipers got lazy today and decided not to self-park.

Any ideas?

This has made me realise that a good wiring diagram, ideally year-specific and printed in colour, will be handy for this and future glitches.

If you know of a source, please let me know.

Sideways

'87 3.2 Sport coupe

 

[937carrera]

A couple of ideas.

If the wipers didn't park and won't work at all now then it could be the switch, fuse, motor or wiring to the motor that have failed.

If the wipers still work, but won't park, then check that the relay is holding in and continuing to supply power via the second live connection to the motor.

I was fixing a "lazy" rear wiper on a 924 last week. It wasn't working and moisture had caused the motor to sieze. I removed the carbon brushes, cleaned & reassembled it & all working again. []

I just looked in my Haynes manual (for '85 - I hate this type of circuit diagram) & see the feeds for the different speeds should be

White / Violet
White / Yellow
Green

Red / White carrying the current to complete the sweep,
Blue / White the intermittent current and
Brown for earth.

I wouldn't have thought that an '87 car would be very different to the above.

Time to get a multimeter to check for voltage at the different points on the motor. You can get a basic one for under a tenner these days, lots more usefull than a test bulb, and its Christmas[]

 

[Guest]

937carerra

Thanks. The fault falls into the second category - wipers work but park where they like.

I have a meter and will check the feeds and earth. The latter could be implicated because the intermittent has gone loopy too.

I found some diagrams for the SC on

http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_82SC_Part4-2.jpg

that might help interpret the Haynes rats' nest.

Sideways

 

[937carrera]

Using the '82 SC diagram you should check for 12V at terminal 53a and work back to fuse 13.

The wiring for the '85 car is basically the same except that fuse 7 is used.

Check the earth by all means but I suspect that the problem will be with the feed. You could always run a wire from the battery to terminal 53a. If the motor parks, then that's pretty conclusive evidence.

 

[Guest]

937carerra

Cool - will let you know how it turns out.

Sideways

 

[Jamie Summers]

Sideways,
It's a really common problem - I had it on my '89 (still a bit temperamental, but better than it was !). The problem usually lies with a dirty / worn out contact on the wiper stalk. It's pretty straightforward to dismantle and clean up with a bit of contact grease. Worth a try before you splash out on any new bits.

Jamie