Windscreen wipers seem possessed

[Trevtherev]

I am struggling to know where to start with this problem. When I operated the wipers to do a single sweep top clear some light mist from the screen, they decided to have a field day and sweep 6/7 times and parked up across the screen. When I tried a single sweep again, they repeated the same, eventually by luck they came to the correct park position. The wipers run in slow and fast mode but seem to forget where the park position is, and wash wipe also shows off by doing what they want in sweeps.
If that’s not bad enough, after the original incident without engaging the front wipers at all in reverse, the rear started. Not sure where to start, seems the motor goes, and the switch seems to operate to some degree. From the dealer I’ve had some less than encouraging help So I was thinking of checking the switch and see if that checks out and then lean towards a new motor, any advice is much appreciated.
Citroën C4 vtr+ 2011 1.6 diesel

[GiveMeABreak]

I'm not sure I understand what your problem is.

The rear wipe will engage in reverse once the front wipers have been activated at some point after the ignition has been switched on. This is normal behaviour and reverse wipe in reverse can be switched off via the Head Unit options.

The front wiper Park position is usually activated once the ignition is switched off and a brief press down on the wiper stalk is made. This is designed to leave the wipers vertically in order for you to clean the windscreen or change the blades. If it weren't to do this, then you would likely tear your paint off when lifting the wiper arms (especially if recessed). Once finished, ignition on and a single wipe command will revert the wipers to the normal position.

If it's anything else then do explain further.

[Trevtherev]

1. When activating the wiper function to sweep the screen once, it goes numerous times and stops anywhere to be honest.
2. In slow or high speed, it again works, but the park position is anywhere.
3. In spray and wipe, the function works, but wipers go for well beyond the normal working time and again stop anywhere.
4. Normally when the wipers are activated and reverse gear selected they sweep as well. But on this occasion the front were not on and parked halfway up the screen and the rear wipers activated.
The engine was running when all these actions were initiated.

[GiveMeABreak]

Ok, so obviously not correct.

My first thoughts are the engine Fuse Box as this controls the relays for the wipers, but ideally, you may need to get a proper diagnostic on the vehicle to see if it has logged any faults. We would really need the codes to get some pointers. If you can get those, pop them up along with your VIN (please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff).

[Trevtherev]

Thanks for that help. I expect I need to have some dedicated software rather than an OBDII reader. I was just going to go for second hand motor and hope it was the answer. I can't really see how that would have sorted the rear motor but maybe it shows how lost i am on this. Just wish cars were as simple as they once were, totally unreliable but you could pretend to have sorted things out

[GiveMeABreak]

Yes, I wouldn't bother potentially wasting money on parts until you have a good idea of the culprit. The motor assembly wouldn't cause the issue with the rear wiper, but a control fault would.

[Trevtherev]

As a quick update today I was able to flip the cover off and waiting for auto electrician to come and read any codes. He did say it might be worth trying an OBDII and see if I get anything. Well didn't expect too and in fact didn't, but the wipers on wash and wipe seem to go eternally now and the only way to stop was to turn ignition off. On the other options, they run and don't stop now unless you turn off and then eventually stop and so far in the park position. Sadly, won't be able to get the codes read until mid next week.

[Hagrid]

I am no expert at all but trying to think logically, it seems as if some signal should be sent somewhere to tell the motor when the wipers reach the park position, but that signal is either corrupted (park anywhere) or missing (not parking at all). Is there some sort of electromechanical switch connected mechanically to the wiper mechanism? Could it have become loose and has now fallen off?

[Trevtherev]

Well, I thought that as well. What I thought was the set-up was the gear on the motor has a lobe on the back which trips a microswitch to orientate the park position. It was frosty, very frosty when it went dappy so never know you might be on the button.

[Hagrid]

A guess one step further: could there be a back-up timer to stop the wipers wiping forever if the microswitch fails? If so, that timer needn't be accurate so might not time out after the same number of seconds each time; and it too could have failed after a bit. Could it be part of the com2000 wizardry?

[Trevtherev]

Hate to agree, but I flip between the motor or the wiper stalk. I hope out of the two, the motor looks the easiest to replace. I'm hoping auto electrician can find some code or point me in the right area. I assume you need some sort of delegated software to access any codes, my cheap OBDII reader gave nothing.

[Trevtherev]

So my plan is to have the codes read (if any) and work from there. Having tried to look at it logically I also understand that if the indicator/wiper stalk control is faulty that it's not as easy as getting a second hand one, as they have to be set to the car. Something about the angle of the car is set to it. (Information from main dealer.) Out of interest, I enquired about a new part, which is just shy of £480. My question is how would you set it up?