Headlamp Wiper.. Odd Behaviour?

[Navy]

Good evening everyone, I have been slowly trying to iron out all the small issues with my 1993 Volvo 850.
This next one has been around for roughly 10 years. When I use the windscreen wash wipe the headlamp wipers work in conjunction however, my drivers side (uk right side when in the car) wiper remains in the up position so far as I can see the blade above the bonnet (Hood..usa). It remains in that position after turning the ignition off and on regardless of the attempts although, after roughly a hour If I turn the ignition on it resets back to park but it needs at least a hour before resetting.
Could this possibly be a relay issue or is it the removal of the wiper motor which appears to be nightmare if Haynes is correct..Ahem!!
Any feedback is always welcome
Many thanks
Andre

[scot850]

Nope. The reset should happen when the ignition is switched off and then switched back on it should reset itself.

These are a real pain and there are many threads out there on how to fix these. With a lot of patience you can dis-assemble the motor and clean and re-grease. However, there are 2 issues that affect these:

1) Broken cog teeth on the shaft. Sometimes depending how bad, you can rotate it to a good section of the cog and it will work. Too much broken off and it is scrap.
2) There is an overload resistor built into the unit. Once opened up it can be seen as a small square flat hole-less washer. These fail over the years. They were installed to prevent frozen wipers damaging the motors, but as they age even regular weather use they will not allow enough power before switching off power to the motor.
Know one has found where you can get replacements, even if we know the value of resistance (that info is out there). I have read of some clever owners who have managed to solder in a regular thermal resistor between the 2 contact sides. Many others just wedge in a piece of copper wire. CAUTION: By doing this you remove the safety in the circuit and if a motor overloads it is on the same circuit as the main wipers and other stuff it can take out the main circuit relay which is not ideal! If you go that route I would suggest splicing in an in-line resistor of a lower value to protect the rest of the circuit.

Note: There are 2 lengths of wiper shaft. I think the 850 is longer than the V/S70 but don't recall for sure so they are not interchangeable unless you swap the rods over.

Neil.

[Navy]

Many thanks Neil, Blimey, I thought this was going to be easy fix. So either way I'll have to remove the electronics air box and headlamp just to gain access. Then remove and disassemble the unit. Ok, I'll have a go and see how far I get. In fairness it resets after a hour so maybe I can live with it if removal becomes too difficult.
Thank you for all the info on the electronic side.....really helpful.
Thanks again
André

[scot850]

Or just disconnect them! The plug is just behind the headlight.

Neil.

[850 LPT]

Or just disconnect them! The plug is just behind the headlight.

Neil.

Agreed, it's what I've done with literally every P80 car we have ever owned. It's simply not worth the hassle and the money.