The car is Clio 3 and the year is 2007. So the wipers turn on for a few seconds, slow down and then they turn off on random position. The weird thing is they must get power because they do turn on, randomly for a few seconds but they do. On diagnostic in UHC, the stalk positions are getting read. In UPC when they do activate (eventually) i can see their speed (timer, slow, fast), parking position is always missing (probably because they stop in random positions). One thing i noticed is when they are activated on fast speed they start going fast then protection activates they switch to slow and then stop. Checked the wipers, greased them, everything seems fine (i can see in diagnostic that it acts the same with or without wipers). Grounding the green wire activates protection. Took the UPC to electrician who said that everything seems fine. I’m running out of ideas and can’t find anything like this (most of the posts are when wipers don’t work at all). Has anybody ever had a problem like this?
No experience w/your car, and don’t know what “UHC” means, but my guess is there’s a micro-switch linked to the ww mechanism that tells it where in the cycle the wiper’s are currently positioned, and that switch is faulty.
Hello, thanks for the reply. I made a typo it’s UCH. What do you mean by ww mechanism
Windshield Wiper Mechanism
What is UCH and what is the UCP?
Where is the location of the micro-switch?
Both are control modules that essentially control non-engine related electronics.
The UCH is the same as a body control module and performs the same functions.
Don’t be surprised if it’s the BCM causing the problem.
Tester
No idea. Suggest to secure a copy of the WW parts assembly diagram.
I’m presuming UCH and UCP are acronyms for french-language words. Similar to how in the english-language the “body control module” is abbreviated BCM.
I assumed it was probably that, but wouldn’t i get a fault in diagnostic or atleast have some other electronics failing aswell? Is it possible that it’s failing and it affects only the wipers?
Will try, and yes you’re right on the acronyms. I guess UCH and UPC are separate control modules which do the same just on different electronics.
If you had a factory level scan tool you could probably diagnose it. And I have never heard a BCM setting a diagnostic code.
A BCM can fail where only one system acts up, or where many systems act up.
It depends on how the BCM fails.
Tester
With this sort of problem, it is always a good idea to first verify the vehicle’s 12 volt battery is working properly & fully charged. Circuits misbehave in weird ways when their power supply voltage is too low. Do you hear any unexplained clicking in the engine compartment or under the dashboard? If so, that’s another indication of low battery voltage.
The only way to see if that is the culprit is to get a new one in?
Or bring it to a dealer so they can run diagnostics,
.
Tester
Battery had 12 volts, but i could test it with another one just in case. No unordinary clicking, can hear relays when wipers start/stop.
Before the first start of the day the battery should measure about 12.6 volts, then immediately after starting the engine, 13.5-15.5 volts. No-clicking is a good sign, battery is likely not the culprit. Easy enough to do the diy’er battery/charging system test still.
I’m noticing you tend to want to replace stuff and see if that fixes the problem. That method worked pretty good for non-computerized cars, 1950’s through mid-1980’s, but modern cars, not so much. Replacing stuff on a hope just introduces more variables into the diagnostic problem. And the replacement part may not be nearly as good quality as the original part. Best to focus on doing the proper testing to figure out what are the most likely part(s) to consider for replacement first, then replace them one at a time, testing again after each replacement. Many modern-car diy’ers would serve themselves better by hiring a pro shop to do the diagnostic, then they can replace the parts the shop recommends replacing as a diy’er project themselves, if they like.
This is actually my job, started working few months ago. I’m using delphi and launch diagnostics.
Begin with measuring voltage on high and low speed wires while the wipers are switched on. If you have power and ground when the motor stops, the motor has failed.
That’s actually the thing i’m trying to avoid and the reason i posted on here. What gives you the impression i want to replace stuff and see if that fixes it? Because i asked if the only way to check if the control module is the culprit is to replace it? Battery was one of the first things i checked and voltage was fine, i’m working on this car for two days trying to pinpoint the fault. I said i can put a different battery because i have access to it and i’m running out of ideas. As i said i can’t find anything like this on the internet (most posts/videos wipers don’t work at all), also as i said in the post i even took the module to the electrician who opened it up and told me that nothing seems wrong with it. The car is at my shop where i’m working and as i said in the reply above i started working a few months ago, i came for advice, not to be insulted.