Polo 1.4 2010 Windscreen Wipers only work at certain angle PLZ HELP :(((

[Annoyedmotorist21]

Hi guys.

Posting here as this seemingly simple issue has become so disheartening and nothing is working; spending my bank balance on parts that don’t make a bloody difference!

Last winter there was ice on my windshield, not snow but icey everywhere. I was attempting to clear the screen when the wiper stopped working. I proceeded to keep driving for months without wipers through storms etc (very bloody stupid, London at midnight pissing down and I’m tryna use tissue to clear it). I then realised that the front wipers intact do work if you pull the stick up and towards you, only at a very certain angle.

I have tried:

Replacing the wiper motor, yet both tested and work
Replaced stalks / switches three times, same thing
Checked all fuses none blown
Bonnet is down.

What the hell could this be? Three months now no car and it’s just burning a hole in my pocket.

I mean you’d think the motor has burned out in the ice, but no it’s not that. It’s almost like there’s an electrical contact somewhere that’s not right and it’s only completing the circuit at that particular angle.

Plz help guys, scoured the internet and can’t find anyone with a similar issue. Sod’s law

Thank you guys

Another thing: the car seems to drain the battery on startup - can’t turn it off then on again without having let it rev or drive after starting again, or the next time it won’t start. This had graudually gotten worse, replaced the battery and it was okay, then it’s doing the same thing again? Could these problems be connected?

1.4 polo 2010 manual

[Annoyedmotorist21]

Oh also, the rear wipers work fine, but neither washer jets work either.

[iichel]

do you have access to a diagnostic tool like vcds?

[Annoyedmotorist21]

do you have access to a diagnostic tool like vcds?

My uncle who’s a mechanic and working on the car, I assume he does. Is there anything specific to look out for? He’s so far been unable to diagnose it, and he’s a pretty good mechanic (lol)

[iichel]

Well, I'd have a look at whether the BCM is receiving input signals.
And whether the BCM is sending the correct output signals.

If so, find a wiring diagram and verify all wires end-to-end.

For the battery drain, your uncle should do a parasitic drain test to see what part of the car is drawing too much current.

[Annoyedmotorist21]

Thank u so much - ironically he has just sent me a screenshot of “signs of a bad body control module” I assume this is the same acronym? Lol how ironic

He’s gonna check out the bcm with that tool you told me to use, could that also be the cause of the drain? Regardless I will send him what you’ve posted, thank u very much

[iichel]

Yes bcm is the same acronym. A broken bcm can indeed be a cause of the battery drain

[Annoyedmotorist21]

Yes bcm is the same acronym. A broken bcm can indeed be a cause of the battery drain

Any ideas how this could’ve happened while using the wind wipers to clear the ice? Like could that in any way have affected the bcm, as it’s very strange it went out as I was doing that no?

[iichel]

I can only speculate, but it might have burned an internal circuit. Cold temperatures often come with moist inside electronics and that combined with high currents (like a stuck windshield wiper) is a bad combination

But it might as well be something else like a corroded plug or ground point.

[RUM4MO]

You might have thought that there would be some form of protection built into the windscreen motor to stop any damage occurring further back the power supply line, but maybe not, and that would leave the BCM output power switching exposed and so now damaged.

In the "old days" there would have been a crude bit of protection, a bi-metallic contact which would go open circuit when the current increased for too long, that seemed to save a few windscreen wiper control relays. Nowadays the size of the switching relay which is internal to the BCM has reduced mainly due to the need to fit everything inside the footprint of the various versions of BCM, and so with reducing size there comes the danger of things being used closer to their reliable limit, which is good if everything works as intended.

Edit:- ah, I was writing that as iichel was writing his posting!

[Annoyedmotorist21]

I can only speculate, but it might have burned an internal circuit. Cold temperatures often come with moist inside electronics and that combined with high currents (like a stuck windshield wiper) is a bad combination

But it might as well be something else like a corroded plug or ground point.

Thank you for this help, do you have any cryptocurrency? I’d like to send u some as a thank you

[iichel]

No, I do not have any , just 'real' money (one could argue the difference between crypto and real, acknowledged money).

But wouldn't it be better to first resolve your issue, before you start rewarding people? Even though I appreciate your offer and gesture.

[Annoyedmotorist21]

No, I do not have any , just 'real' money (one could argue the difference between crypto and real, acknowledged money).

But wouldn't it be better to first resolve your issue, before you start rewarding people? Even though I appreciate your offer and gesture.

Yeah sure bro, I meant after it was fixed (spent all my “real” money on various parts I no longer need haha)! Thanks anyways though bro

[Annoyedmotorist21]

Update. Supposedly fixed when attempting to fix another issue... playing around with cleaning random plugs inside the bonnet. And I mean random, I checked diagrams and nothing I touched seems to be connected to the wiper systems. Weird. Fully fixed.

[iichel]

That's good to hear, congratualtions.