2007 with intermittent brake lights

[otruk]

Hi working on my brothers 2007 gs 1200 and have intermittent brake lights, can be either end when they feel like it! I realise the switches are probably part of the ABS unit, have cleaned all connections etc. The bike has been to 2 motorcycle mechanics so far!!!
Are there any obvious areas to look at?

Thanks

 

[botus]

use a chassis decode tool to check if it has the "normal" later ABS2 setup https://www.mdecoder.com/ - the earlier version has strange unreliable brake light switches (alongside an unreliable ABS unit)

assuming its the one worth bothering with - replace the bulb, maybe the filament is falling off (quiet normal)
if that's not an issue - it might be the ZFE is dying, they are starting to play up on a lot of older BM bikes - I don't think this one does it but the K1300 overall same electrical system does weird and wonderful stuff with a single filament rear bulb

 

[Steptoe]

When you say “either end”,just to be clear, do you mean front and rear brake light switches. Do they both stop working at the same time, or front works and the rear doesn’t and vice versa

 

[otruk]

Both front and rear fail, if you leave it for a time they come back in action. Then overnight turn it on they may or may not work!!

 

[otruk]

I-ABS generation 2 is the unit on the bike. Rear bulbs are good, just about to invest in 911 unit and see what can be done!

 

[botus]

sounds ZFE to me

are you testing with sensible voltage - disconnect and re try with a tip top battery

 

[otruk]

So the ZFE controls the various modules? So if I get a Gs 911 this should show up a fault with the unit?

 

[Santa-2512]

So the ZFE controls the various modules? So if I get a Gs 911 this should show up a fault with the unit?

Should is a bit vague, the gs911 will report on any faults that trigger a cel ( check engine light) and any faults that are stored or currently present, if there is no fault at the time of the scan it won't show anything

 

[otruk]

Its a pain in the butt, I have my son whos handy with electronics trying to use BMW ISTA , hopefully we can get it to talk. I would invest in the Hex gs 911 but if we can get the other working that would be fantastic.

 

[Mistacat]

With the GS911 it will log faults and the number of times they occurred and whether or not the fault is still present.
Like all diagnostics they are limited by the feedback of the item/sensor.