A new type of wiper problem E34 M5

[StirlingM5]

Hi folks, I've seen lots of wiper problems on these boards except this one:
the wipers on my 1989 E34 M5 work sometimes (usually when its not raining) but then won't work when I really need them. They never quit once started, but sometimes won't start. However if I leave the switch in the on position and drive the car around they will come on after 10 or 15 minutes.

This is true whether they are at the high, low or intermittent setting.

Everything else is working fine (radio, sunroof, electric windows) and the fusible link is fine. Fuses seem good, though they did start once when I removed and replaced the #15 fuse (replaced it with the same fuse that is) but now trying that trick, or even putting in a new fuse, doesn't do anything.

Any thoughts?

[joshua43214]

Try jiggling the swtich a bit and see if it starts. replace the switch if that works.

Rap the motor with a screwdriver handle, if that does it, replace the motor.

You can try using contact cleaner on the connector to the motor as well.

[BillionPa]

agreed

[genphreak]

agreed

Changing the fues might have reduced load on the system and caused the voltage to increase overcoming the resistance of the faulty switch/conector. It probably is a dirty contact in the wiper switch, relay or a loom connector. I'd check the connector that powers the wiper motor as it is out in the elements and could be in bad shape by now. Connection cleaner and connection grease need to be on hand- and it is hell to get to unless going in by opening the ebox lid (RHD car or if not from behind fuse box on a LHD car). If that doesn;t do it, I'd do the relay box, fuses, the loom connectors in the dash and around the steering column, and also the instrument panel connections. Of course after all that you might just find its actually the stalk switch . but that's life in a be-emtroubluew Nick

[Bill R.]

with the new ones made by swf. Or open up the relays and look for oxidation on the contacts as well as on the plug in connectors, Clean and try again.

Hi folks, I've seen lots of wiper problems on these boards except this one:
the wipers on my 1989 E34 M5 work sometimes (usually when its not raining) but then won't work when I really need them. They never quit once started, but sometimes won't start. However if I leave the switch in the on position and drive the car around they will come on after 10 or 15 minutes.

This is true whether they are at the high, low or intermittent setting.

Everything else is working fine (radio, sunroof, electric windows) and the fusible link is fine. Fuses seem good, though they did start once when I removed and replaced the #15 fuse (replaced it with the same fuse that is) but now trying that trick, or even putting in a new fuse, doesn't do anything.

Any thoughts?