Dodgy wipers

[kev-rev180]

today while car was parked and the ignition keys were in my pocket both front and back wipers started working and the would not switch of until i had replaced the keys and started the car they then would turn of turned ignition of removed keys wipers then started up again tried to lock car using fob just beeped on unlock no flashing of lights but flashed on opening then disconected car batterie to stop wipers whent through fusses and releys could not find a fault reconected bat wipers still run until ignition was turned on then everything was ok went for drive now everything is back to normel any one had this happen to there car as i am stumped

[suzublu]

Check your ecu hasn't been swimming Time for a plenum check

[kev-rev180]

Thanks for the reply suzublue plenums were done last sunday at the nano meet nothing wrong also had a t4 check at the same time

[suzublu]

Second guess would then be, have you recently fitted a radio

[mystabe]

When you pull back on the stalk does water spray on the windscreen? I've had all kinds of fun with this as if there is a bad earth or short in the wiring to the windscreen washer bottle all kinds of strange things start happening with the wipers

[clf]

Originally Posted by kev-rev180

Thanks for the reply suzublue plenums were done last sunday at the nano meet nothing wrong also had a t4 check at the same time

were the plenums full of water? I have read that water can cause this issue also, and just wonder as the water has been drained (if there was any) , corrosion to the internal components and contacts has begun as it dried?

(have read also that bad earths too can cause issues such as these also - but just saying the above so as not to rule out ECU issues and be chasing red herrings elsewhere )

[kev-rev180]

no all dry no water also no sign of water had masiv rain last night as well

[MarkS]

This has been seen many times before now:

http://www.the75andztclub.co.uk/foru...d.php?t=262704

Opinions differ as to the cause.
Massive rainfall is a recurring theme.

A temporary cure (for the front wipers only) is detailed in post #18

[MarkS]

The rear wipers running is a new one!
Have to think about that one.
Mr Haynes doesn't even mention there is a rear wiper ( on the tourer ), let alone give a circuit diagram.

Does anybody here know which relays and fuses control the rear wipers?

I guess I'll have to revert to finding a use for it under the sills at the jacking points

[MarkS]

Just as a little thought.

If:
1) The car only has one plenum draining tube.
2) The car were to be parked on the natural camber of the road such that the draining tube were uppermost.
3) The rainfall was masiv.

Q) Is it possible that the plenum were to briefly fill up, flood the ECU & BCU, start the wipers going, then drain out of the plenum before anybody noticed ?
Any water inside the car would very quickly be soaked up by the foam under the carpets, hiding that any water had actually leaked in.