Having tinted windows has its advantages, and its disadvantages. I finally got sick of one of the biggest disadvantages, you can’t see through the windows when they are dirty… and the rear wiper doesn’t work.
I originally wasn’t too bothered by the wiper not working, I even planned on removing it completely and just plugging the hole in the glass, but having spent some time driving the car, I soon realised that in the dark if the tailgate glass is dirty or wet, its damn near impossible to see through. Without a wiper, you just cant clear that muck. The rear washer also doesn’t work (the piping to the front is AWOL, and the pump outlet is plugged).
I know the switches get dirty and fail to work, but when the button is pressed I can hear a relay clicking from the rear. No response from the actual wiper though.
So yesterday I started by removing the wiper motor from the window and having a look over it. I knew from ages ago that the motor had previously been submerged in water, and didn’t look good. The wiper spindle bushing through the glass had been leaking badly.
Removal is easy. Well, if yours is as bodged in as mine was, it is. Remove the wiper arm by removing the plastic cap, and the 13mm nut. Remove the two screws on the underside of the motor housing and remove the cover. The wiring needs to be disconnected, the connector should be inside the lower edge of the tailgate, behind the lower plastic trim. My connector was missing, and someone had used spade terminals instead. Yay.
There should be a large nut on the top of the spindle too, but mine was missing. Mine was missing more than I thought, but thankfully I had a couple of spare motor assemblies in my spares, and between the three I had enough parts to make a complete assembly.
And then a washer and big nut on top of that (both missing previously). When this nut is tightened, it actually compresses the bushing against the glass, creating a seal. No wonder mine leaked, it wasn’t compressed.
Before fitting a replacement motor I chose to test one to make sure it actually worked. I whacked some 12V into the motor, and sure enough the replacement came to life nicely. The original, nothing but a big blue spark. Completely seized.
Refitting isn’t rocket surgery, but I did a couple of quick things to make my life better.
Then it was wiring time. I thought this would be straight forward, but no, someone had been here before and made some bodges.
Looks easy enough, just connect the colours up and away I go.
Someone has messed with the car side of the wiring, so instead of the required Red, Brown/Green, Black and Green, I had Green, Blue, Black and Red. I connected them as I would expect, Red to Red, Black to Black, and winged it with the other two (which are for the parking feature, where the wiper will stop at the bottom when the switch is turned off). Nothing.
I suspected the fuse may have blown because of the seized motor in the past, so had a look and sure enough, a blown fuse.
Replaced it, and bam, the fuse blows again. Damnit.
Long story short, red isn’t the power feed. With some multimeter work I worked out that Blue is actually the main feed for the motor, black is of course ground, and the other two are for the park feature. With that revelation I managed to get the motor working when the switch is pressed.
That’s where the random coloured wiring terminates. Presumably this replaces the original wiring. No idea why.
That’s not the worst part though, I can work with that wiring, the worst part is that someone has replaced the rear wiper delay timer unit with a standard relay…
I don’t know why, and from what I can establish, a normal relay wont do the same function as the delay unit. I’m also not sure why, no matter how it’s connected, the parking function blows the fuse. It’s obviously shorting, but without looking further into the relay and wiring, I don’t know why.
I have decided at this point to just abandon the parking function, as I have the motor and wiper actually working properly as it is, I just have to time when I turn the switch off to where I want the wiper to stop.
The one good thing about having no parking function, is that I can park it where ever I damn well please. The wiper normally parks at the bottom, as per above photo, but it always bothered me that it collects dirt and gunk down there, so I parked it vertical (I really need to clean up that excess sealant).
Now I should be able to see out the back in the dark, since it seems to rain every day here at the moment.
Speaking of rain, I also replaced the front wiper refills the other day. I wanted to replace the whole blade, but since they are pin fitting blades, I’m not sure about finding a replacement. Refills work for now.
I did find out the hard way that if your replacement refills have two widths (wide and narrow) and you accidentally fit it into the narrow instead of wide, when you wipe the screen on the motorway the refill will be torn out of the clips on the holder, and then you have no wipers. Thankfully they stayed on the car, so a quick pull over and refit them correctly and I was on my way again.