How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Pete Your Own Question
Pete
Pete, Mercedes Mechanic
Category: Mercedes
Satisfied Customers: 24731
Experience:  Over 15 years experience as a Mercedes dealer technician
14928985
Type Your Mercedes Question Here...
Pete is online now
A new question is answered every 9 seconds

VEHICLE: 2008 MERCEDES C350 SPORT (W204 CHASSIS) 63,000 MI

Customer Question

VEHICLE: 2008 MERCEDES C350 SPORT (W204 CHASSIS)
63,000 MI
PROBLEM: WINDSHIELD & HEADLAMP WASHER INOPERABLE; ALSO, WIPERS DO NOT COME ON WHEN WASHER SWITCH IS DEPRESSED, BUT WORK ON AUTOMATIC & MANUAL SETTINGS IN THE RAIN.
DIAGNOSTIC STEPS I HAVE TAKEN THUS FAR:
1) CHECKED WASHER PUMP FUSE (#13/7.5 AMP), IN DRIVER-SIDE FUSE PANEL INSIDE ENGINE COMPARTMENT: FUSE IS INTACT. CONTINUITY TEST GOOD.
2) WITH KEY/IGNITION IN ON POSITION, DEPRESSED STEERING COLUMN STEM SWITCH FOR WINDSHIELD WASHER PUMP TO THE “ON” POSITION: WIPERS DO NOT COME ON & NO AUDIBLE NOISE OF WINDSHEILD WASHER PUMP (OR HEADLIGHT WASHER PUMP) CAN BE HEARD. NO WASHER FLUID FROM WINDSHIELD OR HEADLAMP WASHER NOZZLES.
3) PROCEEDED TO JACK UP DRIVER-SIDE FRONT WHEEL & REMOVE IT; REMOVED FORWARD PLASTIC WHEEL WELL LINER TO GAIN ACCESS TO WASHER PUMPS.
4) PURCHASED NEW REPLACEMENT WINDSHIELD WASHER PUMP: REMOVED OLD/OEM WINDSHIELD WASHER PUMP & RESERVOIR GROMMET; REPLACED WITH NEW PUMP & GROMMET.
5) ADDED WASHER FLUID TO RESERVOIR
6) IGNITION SWITCH IN “ON” POSITION, TESTED NEW PUMP INSTALL BY DEPRESSING STEERING STEM SWITCH TO ON POSITION: NO PUMP NOISES, NO WIPERS ACTUATING.
7) CHECKED WASHER PUMP FUSE (#13) AGAIN, IT IS INTACT.
8) USING MULTIMETER, PUT THE TEST LEADS ON THE TEST POSTS ON TOP OF THE (#13) WASHER PUMP FUSE, IN PLACE, WHILE DEPRESSING THE STEERING STEM-SWITCH FOR THE WASHER PUMP – ZERO VOLTS ON FUSE WHEN WASHER SWITCH WAS DEPRESSED.
9) REMOVED PUMP WIRING HARNESSES FROM BOTH WINDSHIELD WASHER PUMP & HEADLAMP WASHER PUMP.
10) MULTIMETER: PLACED TEST LEADS SEPARATELY ON FEMALE LEADS FOR EACH PUMP WIRING HARNESS – ODDLY, WITH THE IGNITION IN THE “OFF” POSITION & THE WASHER SWITCH NOT DEPRESSED, I GOT A MULTIMETER READING OF 3.8VOLTS, (SEPARATELY) FROM EACH PUMP WIRING HARNESS.
11) MULTIMETER: WITH IGNITION IN THE “ON” POSITION & METER TEST LEADS IN THE WINDSHIELD WASHER PUMP WIRING HARNESS LEADS; DEPRESSING THE STEERING COLUMN WASHER STEM-SWITCH, A CONSTANT READING OF 3.8VOLTS WAS OBSERVED (SWITCH ON OR OFF).
12) MULTIMETER: WITH IGNITION IN THE “ON” POSITION & METER TEST LEADS IN THE HEADLAMP WASHER PUMP WIRING HARNESS LEADS; DEPRESSING THE STEERING COLUMN WASHER STEM-SWITCH, A CONSTANT READING OF 3.8VOLTS WAS OBSERVED (SWITCH ON OR OFF).
13) SCRATCHING MY HEAD HERE… COULD IT BE THE STEERING COLUMN STEM SWITCH, OR AM I MISSING SOMETHING OBVIOUS?
THANKS IN ADVANCE,
-KEITH-
Submitted: 1 year ago.
Category: Mercedes
Customer: replied 1 year ago.
I forgot to add:
Battery, charging system & electrical system are functioning normally. Car starts strong, battery 10 mos. old & at 12.8 v, static; 13.3v with engine running.Photos attached show voltage reading off headlamp washer pump harness with ignition off, steering column stalk washer multi-switch not being depressed. Got same reading (3.8v - 4.0v) on the windshield washer pump harness, same conditions. Thanks.
Expert:  Pete replied 1 year ago.

My name is ***** ***** I am a professional here at Just Answer. I noticed that your question had not received a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.

If rain or moisture affects this issue here and if any wiring repairs have been done recently on your vehicle I would check and make sure all wiring is repaired and connected properly with all seals for connections being in place.If this has already been checked and found to be o.k. let me know so we can continue.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.Thanks Pete.

Customer: replied 1 year ago.
Hi Pete,Still in need of help. No recent wiring repairs or modifications. Both washer pump wiring harnesses are intact/undamaged. I have not yet checked wiper relay (need assistance identifying/testing), nor the steering stalk wiper/washer/signal multi-switch (need directions & want to eliminate simpler "possibles" before I dig into that).I am fairly technical, been a hobbyist working on cars & motorcycles for a couple decades: don't know it all, but can take direction well. Dealer quoted nearly $500, just to have a look @ this - I have more time than $ right now.Btw, vehicle is a very clean, South FL car, never been flooded, seen a winter, road salt, etc.I look forward to your assistance & hope we can sort this out.-Keith-
Expert:  Pete replied 1 year ago.

Your welcome.Unfortunately I don't have the diagram info on this particular model myself on helping with the testing.I will open your question up for others here to see if someone else can assist further on this as there may be others here that may have more info on what to check or do with this issue.I hope you can get this resolved with ease.No need to reply to my last post here unless it is a last resort as it will keep your question locked to me and others will not be able to view it.If you feel you want to continue to work with me on this feel free to reply at any time but keep in mind in some cases it can be difficult to fully diagnose or help repair this without seeing your vehicle.

Thanks Pete

Related Mercedes Questions