AJH

Hi,

Symptoms: 1.Battery discharging rapidly 2.Glass tailgate opening when engine started 3.Glass tailgate window lock randomly clicking.

Fix: Bought a new switch from BMW for 30 beans. Removed wiper arm, removed cover from other/bottom side of window (two nuts), unplugged old switch plug, removed single nut holding wiper assembly on to window, pulled old switch assembly off, re-assembled in reverse order (used plenty of spray-lube to prevent future corrosion)

Problems: The old switch centre has an aluminium collet that is positioned around the exterior shaft of the wiper spindle assembly; it was corroded solid and no matter how much WD40 and twisting it wouldnt come off. Luckily, Aluminium is much softer than steel so I managed to work away at it with a sharp carpenters chisel until it came off.

Conclusion: A bit of research on tinterweb, a few basic tools, a cup of tea and a nice ham and mustard sandwhich and Ive saved myself a small fortune from the stealers (robbing bastards)

It's already been explained on here many times but if I can help someone out then it cant be a bad thing.

Cheers all for help

eoxaal

My problem now is exactly what you encountered: the center shaft appears to be fused/corroded to the aluminium collet on the switch assembly. I notice that the new switch is all plastic.

Am I correct in guessing that the switch should normally just slide off ( the center shaft isn't threaded)?

I assume chiseling it off means demolishing the old switch entirely? Wold a fine cutting tool, maybe combined with a fine drill, be a good alternative to the chisel?

Your thoughts + any more details on your experience would be appreciated :-)

AJH

Yes, you could probably drill into the aluminium section corroded onto the wiper spindle and then finish with a chisel to release it. If you use a chisel take your time and be careful not to crack the window. The switch should just slide off the wiper spindle.The switch will be unusable after your done.
When you put on the new switch on clean the spindle and put a little lube onto it to make disassembly easier in the future,

eoxaal

Thanks, I'll try that. Good advice about the extra lubrication!

cmg535

I'm not sure about the problem about the nut being jammed - i thought it came off easily enough. However, i have some warnings for you

1. AJH - I'll wager your problem is not the microswitch but the wiring loom. See here: https://5series.net/forums/e61-touri...acement-72751/
   On mine, both had failed. The microswitch had corroded a bit, so you had to press it hard; that was all. The broken/shorted wires in the loom cause it to do crazy things like you mentioned.
2. Before you remove the switch, or attempt repairing the loom I suggest you remove the fascia from the tailgate to get to the lock, and make an emergency release for the glass. If your fault gets worse and you cannot open the glass, you then cannot access what you need to in order to fix it! Connect a couple of wires to the brown/red and brown wires going into the glass window lock. Leave these accessible so that you can get them without unboxing the tailgate. You can open the glass by applying a 9V battery to these.
3. When you replace the microswitch be very careful not to catch the wires on the wiper assembly. Mine had the insulation pinched, and this caused the fault that the glass would open itself when you closed it (effectively the button was being pressed when the glass closed)

eoxaal

@cmg535: Great tip. Do you recall anything about the polarity of the wires if popping the lock with the 9V?

eoxaal

Oh, another thing cmg535: any tips on how to remove the fascia from the tailgate? I'm worried about snapping any plastic retaining clips etc ...

cmg535

Hi. Yes, i think solid brown wires are always ground by convention. In mine i just put a tap on the brown/red, connected to the +ve on a battery and held the -ve against exposed metal on the body. Still, that relies on the brown wire to the lock not having been severed so I recommend tapping both.

To unbox it, i think you take off the two sections on the side by pulling them, and then the tailgate. The tailgate has a large number of screws in it. I have a doc that was posted in German on some other thread/forum but i cant attach it due to the size.

eoxaal

Fixed it. Took some photos of the procedure including unboxing, and will try to post writeup.

The override works like a charm! :-)

Btw: I just drove up to the local Bmw repair shop to ask about the unboxing, and they were very helpful in telling me the exact procedure; which panels to remove in which sequence etc :-)