Preventing rear light corrosion / failure

[SPL]

Not a hugely difficult task, but having read about other people's problems with their rear light packing up, I thought I'd do something to stop mine going the same way.

My bike is a year old and has done about 9.5K miles, yet was already showing signs of the terminal corrosion that has led to problems on other bikes.

So, this is how I fixed the problem.

Firstly, take off the lense and put a little silicone grease around where it seats onto the reflector.
At the same time, blob some into the two holes in the base of the lense.

Hopefully this will stop any water getting in this way (it hadn't on mine, but better safe than sorry).

Then remove the bracket that holds the number plate and rear light cluster.
There's three torxs screws that hold it in place on the underside of the rear sub-frame (see picture).

 

[SPL]

With the bracket loose, you can see the 3 connections on the back of the light cluster, and why they can corrode:
There's sod all protection for them

See picture below, in which I've already disconnected one of the connections.

 

[SPL]

I cleaned up the connections with a quick squirt of WD40, then cut the thumb off a pair of heavy duty rubber gloves to make a cover.

After making a small hole in the tip of the thumb, I passed it over the 3 wires, so that the base of the thumb is closest to the bulb connections.

See below;

 

[SPL]

Once the connections are back in place, you can stretch the home-made rubber boot over the whole lot so that they are protected from the elements.

Once it's fitted a couple of zip ties will ensure it stays seated and close the hole that the wires were threaded through (picture below).

Then it's simply a case of fixing the bracket back in place with the 3 torxs you removed at the start.

Job done

Like I said at the start of this thread - not difficult to do (in fact, why don't BMW just put a rubber boot on in the first place ) - but might help someone avoid a problem in the future...

 

[SMB]

On my 2008 GS Sept, the rear light is sealed (LED) and the connection plug is way into the tail of the bike, no chance of water ingress. Sorted!!

 

[Snoopy]

LED rear light is £100 if you get your dealer 10% discount and solves the problem of this and servos disabling on older bikes if bulb blows. Job done.

 

[Wapping]

Good one SPL nad cheaper than a £100 LED replacement.

It reminded me of the rubber glove shield I used on my old Mini's distributor.

I an sure I read somewhere that a condom (preferably unused) will perform a similar trick and can be heat shrunk.

 

[SPL]

I an sure I read somewhere that a condom (preferably unused) will perform a similar trick and can be heat shrunk.

I did consider it, but wondered how long it would last
Mind you, if I'd known they heat shrink, I might have given it a go
I reckon a bicycle inner tube would work as well (to seal the electrics, not as a prophylactic!)

 

[davidgibson999]

This is a bit late for me as I just picked up a new taillight unit from the dealer today
I'll get a condom out for the new one though

 

[davedyer]

I an sure I read somewhere that a condom (preferably unused) will perform a similar trick and can be heat shrunk.

Condoms shrinking with heat? So that's why!!

 

[G4]

Have an 07 GSA and mucked around with different rear light options because of bad design. Have now had fitted for a few months a rear light unit from an 08 model, worth every pound. And as pointed out the new unit is sealed and in my opinion, though worth not a lot, its a lot lot better.

 

[Sgt Bilco]

Nice one SPL.

Had 2 issues with mine so regularly dose it with WD. First time it happened had the LampR warning on on the dash imtermittently although everything was working. Took the rear lens off to see the internals coated in shite. Quick clean up, new bulb and no problem. 2nd time was just as I took it in for the last service so my friendly dealer replaced the rear light FOC as it`s a common problem.

Think I`ll do your mod when the weather goes above freezing.

 

[davidgibson999]

stuck the new tail light unit in yesterday and put used your glove thumb trick - hopefully it will prevent a repeat. Good idea mate!

 

[AndyW]

Another ukGSer posted his DIY solution a while back, making a plastic cover to seal the back of the light unit...
Waterproof R1200GS Rear Light Electrics