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Replacing rear wiper switch.

5K views 24 replies 6 participants last post by  Mike Kilo 
#1 ·
So, I have scoured this board and have not been able to find any reference to how exactly one changes out a switch on the front center panel. If it is out there somewhere, I apologize in advance.

My rear wiper will not work when the switch is pushed and will only work when the front wipers are on and the car is in reverse. I understand that this is a standard (on many cars, actually) operational procedure, and, to me, indicates that the switch is probably bad - the rear washer does not run when the switch is pressed in that direction either.

My question is: what is the best way to replace a switch on this panel? I have looked and it is not obvious if a switch can just be pulled out or if the panel has to be removed and the switched changed out from behind the panel; and if so, how should one remove said panel to access the switches? I really do not want to damage the panel, as the interior of this ML is in REALLY good condition for its age.

Any assistance would be greatly appreciated!
 
#4 ·
#8 ·
NO JOY... :(

Well, the supplied directions and suggestions were great and I was able to remove the panel and change out the switch (and clean up and fix a few other small items I found with the panel and switches) with no issues whatsoever.

Thanks to 43sqd and jrlaw for the assists.

HOWEVER, the rear wiper is still not working form the switch (as mentioned previously, the rear wiper DOES work properly when the front wipers are on and the car is put in R). Nor do I ever hear the rear washer motor running.

The only fuse I find labeled for the rear washer is also the fuse for the radio, and the glove box/interior convenience lights, and as all of those other items are all working, that fuse is good.

So then I went back to inspect the wiper and washer...ummmmm, WHERE is the washer nozzle supposed to be? I see nothing that would involve squirting fluid onto the rear window anywhere on the back to the truck. the only thing I found was this spot of what appears to be black silicone or RTV filling a small hole in the very rear center of my roof (see photos)...


Is that where a nozzle should be? I am trying to find a diagram somewhere, but figured I would ask here as well.

TIA!
 

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#9 ·
So, disregard some of my last.

I answered my own nozzle question by finding a post by AC_ML here. As I look at the center of the nut holding my rear wiper arm on, I see the nozzle hole from the broken off nozzle. There is a blockage somewhere in the line - the broken nozzle itself I am assuming since I had to remove all three of my front nozzles and clean them out to get the front ones to operate (sort of, one barely drizzles still - gonna have to rework that one, and I kinda munged up another one of them, it still spits water onto the windshield, but it isn't pretty). I know this because I swapped washer lines from the front motor to the rear motor and actuated the front pump - heard it operating but nothing out of the back, kind of like it used to do before I cleaned the front nozzles.

So, time to purchase new nozzle and see what I get from that.

HOWEVER, still doesn't do anything to resolve my rear wiper not working from the switch issue...

And now I have much curiosity about that plugged up hole in my roof....

Two steps forward, one step back, and a stumble off to the side....
 
#12 ·
Yes.

I have the original owners manual that came with my truck.

I have read that page probably five times now.

Am I missing something?

The rear wiper motor is known to be good because it will actuate as advertised when front wipers are on and car is placed into R. So none of the troubleshooting steps I have been able to find apply to MY situation, they all have to do with checking voltage and lubing shaft, and cleaning rear wiper motor. The motor has voltage and operates properly.

I AM UNABLE TO ACTUATE THE REAR WIPER USING THE SWITCH ON THE CENTER PANEL.

Neither will the rear washer seem to operate when I press the switch on the center panel, but this is less of a concern to me.

Any troubleshooting tips or suggestions beyond changing out the switch, which I have already done, would be appreciated. I focused on the switch since the motor itself functions, but apparently that was not the issue.

Thanks.
 
#16 ·
Hallelujah, Praise the Lord, and Pass the Potatoes, IT IS FIXED!!!



Checked all the fuses in the passenger footwell compartment. Found both of my 12v outlet fuses blown (I already figured as much since neither worked, just hadn't checked yet), but the one for the rear wiper motor was good.

Check fuse #16 in the engine bay fuse/relay box. Replace if necessary. You can test both sides of the fuse for voltage - power is supplied when key is in position 2.

If that checks out OK you're down to a wiring fault or a rare AAM problem.
I DID check fuse 16 just for S&Gs...it was good.

Fuse #16 in the engine bay fuse/relay box does not service the wiper system in any way, front or rear.

See attachment for all fuses servicing the wiper system in MY 2000.
Yes, thank you once again, 43sqd.

The label for fuse 10 in F1 was radio/rear washer/glove box/convenience lighting. I figured that since my radio was working fine (so I thought) that the fuse was good - I hadn't actually inspected it yet. I never really noticed the glove box or mirror lights, since I hadn't opened the glove box in the dark and never used the vanity mirror in my sun visors, so I had no other indication this fuse might be suspect. But, since I was in a fuse pulling mood, I popped #10 out, and lo and behold, it WAS blown.

Inserted the handy spare from the cover for F1, got into the cabin, turned the key, pressed the rear wiper/washer switch and BINGO, normal operation. Never would have thought that the rear WASHER fuse would keep the switch from actuating the rear WIPER, but that seems to be what was going on. In my case at least. And I learned that I really didn't have to manually turn the radio off and on every time I turned the car off and on, as it seems the "radio" part of that fuse provides the power for the current operating state memory of the radio; sweet.

Little by little she gets closer to her proper condition...

Thank you all for your help and advice.

Now I just need to get that darn rear nozzle so I can do something besides squirt the windshield of the car BEHIND me....:grin:grin:grin
 
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