problem, octavia rear wiper motor

[fatfires]

Hi, I have had my wiper motor pack up so I have got an aftermarket replacement but it wont work the fuse 41 is OK and there is power to the plug but no sign of life when the stalk is pressed to wash or wipe, no sounds from under the bonnet either, any advice would be gratefully received, keep it simple please!

Thanks, Tony

[pikpilot]

Have you tested the motor you took out? There is the possibility that the it is not the motor but the control signal.

I don't  know about the '08 model but probably the same as the facelift models where the motor is controlled by CanBus. 

Check for broken wires in the wiring tube that takes the wires from the hatch to the body.

 

[roy@ck]

Hello fatfires and pikpilot,

I've the same problem with my Octavia Estate, the wiper motor does not work, checked the 15A fuse - OK, checked for 12v at the connector plug (when stalk pushed forward one click - ignition ON) - OK.

Disassembled the wiper unit, removed the printed circuit board ( CanBus ? ) from the gearbox housing, applied 12v to the motor - working fully OK. So I'm assuming faulty circuit board - Is this replaceable as a spare or aftermarket - after all somebody is making them for VW?

I hate discarding perfectly working mechanisms just because of failing electronics.

 

Any information or Ideas gratefully received. Many thanks - Roy

[pikpilot]

I doubt you would get a spare board. Best bet would be a motor from a scrap car dealer but check part numbers are the same as I suspect later units may have electronics with more features.

 

First I would check your old board for sign of corrosion or dry joints (look for cracks in the solder or dull/crystalline appearance). Resolder as appropriate.

[roy@ck]

Hello pikpilot,

Agreed a replacement board as a new spare would be like finding a gold watch in your cornflakes. Have been looking at motor units from breakers and have noted the variants, even when listed with the correct part no for my model. I'll give the board a really close look over under a magnifier, to see if I can find a possible cause.

From my previous look at the board, all of the components are of the sub-sub miniature size, like that you'd find on a computer motherboard. You never though I might get lucky and find something fixable!

Your advice is very much appreciated, and thank you for your interest, I'll let you know what I find.

 

Many thanks, Roy

[roy@ck]

Hello pikpilot,

Apologies for the time lapse, but have now had a really good look at the board under an illuminated type magnifier, and can find no signs of corrosion of the soldered joints, contact pins or electrical overload and breakdown. The board on the face of it looks good as new. However, there are a number of integrated circuits on the board and I suppose that there could be an "internal open circuit" somewhere causing the problem. So , I'm thinking it's a replacement/new wiper unit.

 

Many thanks for your contribution, best regards - Roy