1200 GS rear light cluster corrosion.

[davidgibson999]

The rear light unit was the ONLY thing ever replaced , when my 'bike was under warranty.....

It is a complete piece of crap, and literally worse than the light unit fitted to a Honda 90.

Note....If you find that your despite changing the bulb you still get the 'light faulty' indicator, you may have to use a genuine BMW bulb.....something to do with the bulb's electrical resistance, and how the bike's computer meaures a non BMW bulb as 'faulty'....Happened to one of the guys here....

HTH....

ok - i'll try this as interim measure

 

[ChrisDolphin]

Same happened to my GSA at the end of last year - 8 days after the 2yr warranty ended.....£55 to replace at North Oxford. Tried to get under warranty but BMW Customer Support said they weren't 'obligated' to replace. Had to have a replacement on my 1200 also....should have remembered and got it checked within the 2yrs.

 

[Pukmeister]

I just did a fix on mine during my recent service, by stripping and cleaning the unit then wrapping all exposed wiring in self-amalgamating tape to keep water/salt out then liberally spraying inside with ACF-50 before reassembly.

I also bent the connectors towards the lamp slightly to ensure better contact and avoid the dreader LAMPR warning.

 

[pistonbrokescooby]

light

hi all
after reading the thread ,just had a look at mine , its ok at the minute ,not for long eh , one word comes to mind dismal affair ,all the wires and connection on show ,what a bad design ,out a sight out of mind . nothing to stop the elements getting to it , took the red lense off ,undone the bolt under the mudgard holding the assembly in ,still not coming out , is their bolts under the rack to undo or just give it a tug? looks to me two bolts under the rear rack to get to ?? .

to anyone who rides in the wet are on borrowed time with the rear light unit.
will be quite easy to waterproof once the light cluster is out .
bit of silicone grease on the terminals and a rubber shroud over the bulb holder should do the trick ,water and road crap gets up under the number plate by the looks of things and lands on the whole lot .
can't be a engineer who designed that .

 

[Pukmeister]

Scooby, I think there are three or four nuts you have to undo to get it off, one at each side and one in the centre IIRC. Undo the removeable panel in the rear undertray above the numberplate hanger and you'll find the hidden nuts you need to undo in the recess beneath it.

 

[Rong]

cheers but i think that works on the same principle as NN unit which plugs into bulb socket...

No these don't work the same way as the NN ones as they don't use any of the existing light fitting, they are a replacement. As such, whilst they work, you will get the bulb failure indicator appearing on the dash as the LEDs haven't got the same resistance as the origianl bulb. The NN ones have a dummy 'bulb' (resistor) to trick the system, so you will need to do something similar either with a resistor wired in parallel or with a covered up bulb wired in parallel.

Once done they are an excellent rear light, nice and bright.

 

[pistonbrokescooby]

light cluster

hi pukmeister
thanks, did look at the panel underneath with the 2 star jobbie bolts , just didn't want to make any unnecessary pulling apart but looks like i will have to anyway ,weekend job now .

 

[Prattapillar]

Funnily enough the same thing happened to me the other day, thought the bulb but working perfectly when examined. Went to remove it but couldn't get it out so took the light unit off completely and was amazed to see how exposed it was and the level of corrosion in there. I managed eventually, after a liberal application of WD40, to get the bulb out, breaking it in the process then took all connectors apart and cleaned all exposed terminals with emery cloth, couldn't work out what to do with the insulated terminals so decided to douse it all liberally with ACF, put it all back together and if the LAMPR warning was still there cut off and replace the insulated connectors. Fortunately the clean up worked.

The hardest part of the whole procedure was splitting the IP rated connector for the whole cluster, which in my view is pointless anyway given that 2 inches downstream every other connector is open to everything the rear wheel throws at it. German engineering? My arse!

 

[SPL]

Bit late now, but there's a guide to how I sorted the problem on my bike here:

http://www.ukgser.com/forums/showthread.php?p=1668201&highlight=rear+light+corrosion#post1668201

 

[pistonbrokescooby]

light

hi all
sorted , undone the two star bolts under the mudguard and the lot drops down, ac 50 the lot , cut a piece of rubber up and placed over the top of the bulb holder ,3 inch strip,1 1/2 deep,just tucked under the recess , then a piece under the bulb holder approx the same size ,no water can go directly onto the bulb holder now ,once bolted back up into framework can't fall out . might get damp but won't get lagged in crap .what a poor design ,70's jap bikes were sealed better than that .

 

[SHORTLEGS]

got the dreaded "Rear Bulb Failure" warning a few weeks ago, checked the bulb, both filaments working fine, so read up on the problem here and got suitably depressed.

Finally got the ACF 50 this week and dismantled the light assembly. What a crazy set-up, nothing to keep crud from the wiring and contacts.

However there actually was no sign of corrosion (the bike leads a sheltered life), just dirt, so cleaned what I could and squirted on some ACF. No change, warning still there

Hmmmm, maybe I should try another bulb - borrowed one from another rear light and problem cured

There's a lesson in this

Now I've just got to get the silicone, cut up the rubber glove etc and do what MBW should have done in the first place