new to all this

Well-Known Member
I thought I would tackle the front wiper system last weekend.

It was very squeaky when engaged but one day the wipers/motor just stopped.

I purchased a new wiper arms, gears and motor and new cable. Although fiddly, fitting wasn’t the issue. The issue has come when I plugged the connector in and get nothing from motor when engaging switch on column.

I had a look at the fuse box and noticed the one for the wipers had blown but from the state of it that didn’t look recent. I changed it yesterday and still nothing. I have chased the wire back and looked at the column lever and all seems to be intact.

Electrics are not my happy place (picked the wrong vehicle I know!) and I have a multi meter but I am just a little lost as to where to start.

I know wiper systems are a common problem so any advice would be appreciated as at the moment I can only drive when no chance of rain!
 
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I have looked at my relays 3 in total behind the fuse box.

I have found the following relay diagram and it appears that the single one in its own (no 9) is the wipers https://www.lrworkshop.com/diagrams...ectrics/relays/relays-to-(v)-la939975_52886#9

Mine are however the other way around, with 1 on right if you are facing out of the vehicle and two on the left. These two look very old but don’t appear on diagram to be the motor one but the other one (suspect wiper) looks a bit newer -

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There are a lot of different relays and I am not sure which will replace this one. Any ideas?

also I don’t know if this will solve ultimate problem as it could still be stalk switch.

any words of wisdom?
 
All I can say is in the previous thread did he not find somehow it was a flasher unit in place of the wiper 1;). I don’t know your year wiring. Just thought yours would have been covered in the diagrams in that thread.

You need to get your multi meter out and first just check for voltage at motor and in/out of stalk, and of course good earths.

Or even check continuity on wires from motor to stalk in various positions (battery disconnected) draw it on a piece of paper.
Continuity doesn’t always prove the circuit as it could breakdown when you apply a load, but it’s a good place to start.
It’s a learning curve;).

J
 
As the battery is just next to the motor it might be worth using some lengths of cable direct to the motor to see if the issue is the new mechanical parts or if the issue is the wiring. It is fairly easy for one of the wheel boxes to lock and the whole wiper system appear to not be working but is it just “seized” solid and cannot move. You also haven’t changed any of the electrical parts. What you have changed is the mechanics so I would be starting there.

The relay is also only used for park and intermittent/slow from my understanding of the 300tdi wiring diagram (linked thread above). Not sure if it is the same for earlier models.
 
As the battery is just next to the motor it might be worth using some lengths of cable direct to the motor to see if the issue is the new mechanical parts or if the issue is the wiring. It is fairly easy for one of the wheel boxes to lock and the whole wiper system appear to not be working but is it just “seized” solid and cannot move. You also haven’t changed any of the electrical parts. What you have changed is the mechanics so I would be starting there.

The relay is also only used for park and intermittent/slow from my understanding of the 300tdi wiring diagram (linked thread above). Not sure if it is the same for earlier models.
Thank you.

Yes, from memory mine never had intermittent. It was just slow, fast (ish) and single wipe. nothing else has been changed or damaged aside from fuse which looked like it had been blown for a while and rusted.

I will connect some wires as suggested. On my search I found a diagram of the terminals (think might have been your thread) to test. What fun.
 
A car bulb in a holder [ side lamp size ] with a crock clip on one lead and a point probe on the other is a simple handy tool when figuring electrics.
 
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As the battery is just next to the motor it might be worth using some lengths of cable direct to the motor to see if the issue is the new mechanical parts or if the issue is the wiring. It is fairly easy for one of the wheel boxes to lock and the whole wiper system appear to not be working but is it just “seized” solid and cannot move. You also haven’t changed any of the electrical parts. What you have changed is the mechanics so I would be starting there.

The relay is also only used for park and intermittent/slow from my understanding of the 300tdi wiring diagram (linked thread above). Not sure if it is the same for earlier models.
Would I connect the positive to point 3 and the negative to point 1 or 2 in test diagram 1?
Would I need to earth it as well?
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still trying to trace the fault.
 
Would I connect the positive to point 3 and the negative to point 1 or 2 in test diagram 1?
Would I need to earth it as well?

The earth is the battery negative so you don't need to worry about that. Looking at the diagram to test normal speed it looks like you need to connect battery positive to point 5 (bottom left spade) and battery negative to point 1 and 2 (horizontal spade and top right spade). You can then leave the negative connections in place and move the positive to point 3 (top left spade) to test high speed.

You can can also just test the motor and bypass the park switch all together. if you remove the park switch and unplug the three spades (red, blue, yellow) you can then link power and earth direct to these three cables to test the motor itself in isolation. From memory the blue is earth (battery negative) and the red and yellow are for the two speeds, but I would need to look it up to confirm.
 
Well today while sorting out a brake light issue I tried my luck with the wiper motor. Sprayed all the connectors and attached the earth securely. Everything started to work! Such a relief.

Just the park leaving the wipers at 12 o clock but I believe that’s because the crank gear must be in the wrong start position. Can’t fact sorting that at the moment so will just enjoy my wipers in the rain for a bit!

Thanks for all guidance along the way.
 

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