S40 haunted wipers!!
 

Hi there Volvo folk,

I'm new to Volvos. Really like my '04 S40 2.4 which I got last year.

The only niggle is the (seemingly common-ish) problem with the wipers randomly coming on!

I've trawled the forum and have had the ECM (?) unit out for cleaning. This didn't work, so I've done the same with the fuse box under the bonnet. No joy.

Perhaps the connections to the motor are corroded. However, I can't seem to get to it though, as the windscreen cowl won't budge.

Any help gratefully received :regular_smile:

do you have the auto wipers option which automatically come on when there is even a little drop of rain? maybe check the sensor for that?

Hey man, thanks for replying.

Yes, I do have that option I think. I haven't used it, as far as I know though..

Do you know where the sensor is located by any chance?

Rain sensor is top center of the windscreen... but auto-wipers are off when you start up until you turn them on... you see the little wiper/raindrop icon in the bottom LED above the mileage

Interesting..

When the wipers come on by themselves, I try switching the 'auto' function on/off but the icon never lights up. Not sure if that proves anything though!

Is the sensor in the module that has the rear-view mirror attached?

Does it have it's own fuse?

Well, it's not the sensor.

The wipers came on again of their own accord. I found the sensor and disconnected it.

The wipers kept going...:confused_smile:

Try pulling out the wiper control stalk and clean the contact points. I heard of someone replacing it because it stopped working, maybe it can also wear off in the way so it shorts out?
Otherwise it may be something in cars brain triggering it and Vida may actually diagnose it, if you have an access to it?

Thanks for the suggestion. I'll try this next.

Since my last post, I have taken the wiper motor unit out and had a look at it. It's not the original and seems in good order, as do the connections. No signs of corrosion anywhere. There's a circuit board in there which could be bad I suppose.

I just decided to just remove the fuse for the wipers for the time being though.

However, someone suggested putting the fuse back in and disconnecting the rain sensor. So I'm trying that. Haven't driven it much yet.

Don't have vida access but I have a code of P0194 'Fuel Rail Pressure'

In previous post you mentioned you already did, so it still engage when sensor disconnected or not? Maybe it is just a sensor going haywire...

I agree with you. I thought the rain sensor was faulty.

As I mentioned in the previous post, I tried disconnecting the rain sensor when the wipers had already come on. So I (incorrectly) assumed the rain sensor was OK and plugged it back in.

However, even with the sensor permanently disconnected, the wipers have again started of their own accord.

I have taken the fuse out and am considering a new wiper motor. They seem cheap enough on ebay..