Rear Wiper Motor problem

[ugwaraich]

folks,
I have yet another issue here with my 316ti Compact (2003 E46). In the past my rear wiper randomly worked, like somtimes it used to work but most of the times it used to stuck even if I give it a push manually with a hand. Now recently, it just completely went silent and no movement.


I myself am an electronic/electrical engineer so thought of fiddling with the motor myself(as I may learn something new and might be able to save £160) and first check whether it is the wiring issue or motor issue, so I took the rear wiper motor off my car on saturday, I want to understand a few things here:

There are two connectors that connect to the Bosch Electronic panel mounted on the motor assembly. The first one with 3 pins

1) Earth
2) +12V
3) 0V

I checked the supply it was coming uptil this point. Then the second connector which consists of 6 pins.

Now I dont know what is the signal coming through those pins and which pins are for wiper movement and which ones are for screen washer pump(could be a Pulse Width Modulated/voltage amplitude signal)? does anyone have any information about these details? I presume that information like this is confidential to BMW, so its hard to get any info on this, but still if anyone's got any experience/info please pass on.

I think it might be worth checking whether the signal is coming to that connector when I trigger the switch from steering wheel for rear wiper?

I want to make sure that there is no wiring issue before I buy another motor and that the motor I have is faulty so that I dump it, otherwise its not worth dumping a working motor is it?

Thanks in advance!

[leeky]

hi there! iv just got the same problem on my 2003 318ti compact! iv got no wiper blade movement and no washer pump action! just wondering if your still about this place have you got any more info on fixing it? or how did you fix yours? cheers!

[ugwaraich]

Hi Leeky, Yes, I took the chance and I bought a used working motor from a scrap yard, and found out the problem was actually with the motor itself dont know if it was mechanical or electrical problem but I had to replace the motor. You can find many links online if you google used car spare parts online you can fill in the query and give your part number and your car details then you can buy the motor with some warranty. Once you get your motor you can take off the trim under the boot lid of your car and simply replace your motor, it is very easy. Good luck

[cmptrwiz]

this is the 'inside ' of my former rear wiper motor.

Would suggest cleaning/greasing any rear wiper motors that are still working. The rear washer fluid goes straight though the motor's gear area and the resultant 'rust/gunk' jams the large pink gear, effectively stripping the gear

Unfortunately motor still works and the windshield washer fluid flows through it again, if the gear was replaceable it would work just fine...