2005 xc90 wipers randomly coming on.

[xarlock667]

Originally Posted by poiuytre111

Given the age of the car, I personally would consider a bodge repair i.e. control the wiper from a new switch entirely independantly.

You appear to know that the blue wire is causing the problem so what happens if you cut it and then perhaps switch the wiper end of it to either earth or 12v ?

Older cars would typically have two live feeds to a wiper, one to start operation and a second that routes through a contact in the gearbox so that it can continue after being turned off to return to the park position. (On a front wiper there would be a third connection for the high speed setting.) If you provide a switched feed to the first of those two power connections you might have more control of your errant wipers.

I had actually thought of this, I consider it more than moderately stupid to run ALL a vehicle's electrical connections through a single module that is not air tight, and sealed. Get some water in there and you screw your whole vehicle and can conceivably even cause a wreck. That said, I want to keep the vehicle as original as possible.

[Clan]

Originally Posted by xarlock667

I had actually thought of this, I consider it more than moderately stupid to run ALL a vehicle's electrical connections through a single module that is not air tight, and sealed. Get some water in there and you screw your whole vehicle and can conceivably even cause a wreck. That said, I want to keep the vehicle as original as possible.

The way to repair this is as i described in my post#8 above .
The reason the wipers go all the time is because the communication network isn't working properly . The wiper motor relies on a good OFF signal to keep the wipers off , otherwise by default with no instructions to turn them off they run all the time for safety ...

[Harley Dave]

So - given that he has swapped out the CEM, could the problem be with the multi-way plugs?? (which presumably haven't been changed - yet)

Cheers

Dave

[xarlock667]

Originally Posted by Harley Dave

So - given that he has swapped out the CEM, could the problem be with the multi-way plugs?? (which presumably haven't been changed - yet)

Cheers

Dave

I have not swapped them, and I am not sure how it would be done. Whatcha got? And does ANYONE have a wiring diagram? That would be epic!

I DO know that whatever is causing the power surge happens before the relay. I know this because when I pulled the relay, I checked the socket for power and it was going on and off randomly as the wipers were. Can anyone check into this and find out if the power comes before or after the CEM?

[xarlock667]

Originally Posted by Clan

The way to repair this is as i described in my post#8 above .
The reason the wipers go all the time is because the communication network isn't working properly . The wiper motor relies on a good OFF signal to keep the wipers off , otherwise by default with no instructions to turn them off they run all the time for safety ...

Remember, I swapped the CEM for a good one and the problem continued without even pausing. I would LIKE to replace the CEM just because of the corrosion that was there, but it is not up to me. And while the do run, it is off and on, not continual.

Thanks for the help, keep it coming!

[SwissXC90]

Originally Posted by xarlock667

And does ANYONE have a wiring diagram? That would be epic!

Epic is easy:
http://www.volvowiringdiagrams.com/?...ing%20Diagrams

[xarlock667]

Originally Posted by SwissXC90

Epic is easy:
http://www.volvowiringdiagrams.com/?...ing%20Diagrams

You are an AMAZING person!

[xarlock667]

FINALLY!!! There is a set of wires under the OVERHEAD CONSOLE. One had been pinched almost in half and it was causing a short circuit! I cut and spliced the wire, packed everything as neatly as I could, and then I tested it... VICTORY!!! NO CEM, NO WIPER MODULE, NOT A FUSE AND NOT A RELAY!!! a stupid damned pinched wire!

THANKS TO EVERYONE FOR YOUR HELP!!!

[aslan]

Originally Posted by xarlock667

FINALLY!!! There is a set of wires under the OVERHEAD CONSOLE. One had been pinched almost in half and it was causing a short circuit! I cut and spliced the wire, packed everything as neatly as I could, and then I tested it... VICTORY!!! NO CEM, NO WIPER MODULE, NOT A FUSE AND NOT A RELAY!!! a stupid damned pinched wire!

THANKS TO EVERYONE FOR YOUR HELP!!!

Excellent! Wish it was this a cheap fix for previous my CEM issue. When you say the overhead console, you meant the light assembly in front the rear view mirror?

[gmonag]

Presumably the wiring to the rain sensor.