meth

Dear All, newbie on road and need direction to do my own fix for the CLK.

Got a used CLK and found the windshield washer pump is not working. Took the pump off and found it has no power (with the washer button triggered on the multi-function switch.) Meter works for it does read the head light power. Wiper works most of the time but fails occasionally. From other posts in the forums, I suspect it's the multi-function switch since there's no fuse for W209.

Is there a way I can trigger the washer in the engine bay so that I can better conclude it's the multi-function switch? Also, I read others could check the pump by plugging it elsewhere (i.e. headlight washer). I could not found the same plug elsewhere in mine. Any other way to check for the washer pump? Thx!

sailorben

Yes I was going to suggest swapping the windscreen pump for the headlight washer. They should be adjacent to each other in the tank.

meth

My model does not have the headlight washer but I did see another wire goes together with windshield pump power. The wire is with a smaller connector which doesn't fit the washer pump.

Since my mutlimeter could not see any current with the washer switch triggered, I am more incline to believe the pump is good. it would be great if I can trigger the washer pump to run inside the engine bay so that I can limit the problem to the switch or anything upstream.

sailorben

Apologies I thought all w209 came with headlight washers. Both my present and my past w209 had them, even without xenon headlights fitted. The washer pumps themselves are very cheap on eBay anyway.

If you could find an Indy with SDS that'd be able to tell you, but for the £20 or so that'd cost, you could just buy a new pump or switch, or both.

Yidney

Only takes a minutes to access the washer motor in front of your left wheel. Just drop that lower section of liner. Then if you have a battery charger, or a battery, just unplug it and jump and see if it runs.

meth

I have taken the washer pump off and found the connector has no power with the multifunction switch pressed. guess i will do so again to jump the pump just to make sure the it's not faulty.

Hoserbenzo

I though my pump wasn't working before. Make sure you press the the button harder. You will feel a second "click". Try that before taking out the pump.

meth

it's fixed! well, not sure what went wrong initially, but it was actually the pump not working. somehow my car does not always gives power to the pump (including the wiper) by pressing the multifunction switch with stuff opened up. after I put everything back together and wala! it starts shooting jet to the windshield. Thank you all for the tips!

curious though. shouldn't the CLK shows warning if the windshield water is low? after I replaced the pump, there's no water in the reservoir. But I did not see any warning on the dash. any idea?

Rudeney

It sounds like you have a problem in the wiring harness on the front end of the car. The washer pump, washer reservoir level sensor, and the coolant reservoir level sensor are all wired together. If one is disconnected, it can cause faults on all of them. For example, if you unplug the connector to the washer pump, you'll start getting "low washer fluid" and "low coolant" errors. I'm not sure why this is, but maybe they are in series and uses various levels of resistance to report the levels?