BMW R1200RT/R1250RT Forum

The side marker bulbs did not burn on my R1200RT.  However, when I replaced with a new bulb, the bulbs burns all the time.  Key on, key off, makes no
difference.  Any thoughts or suggestions?

Are we talking indicators and what bike?

RTman10 wrote: Are we talking indicators and what bike?

You on the sauce again RTman10, the bike is in the title lol but I am curious as what is a side marker light?

Spencert231 wrote: You on the sauce again RTman10, the bike is in the title lol but I am curious as what is a side marker light?

Yes but one of those old air cooled things or a proper one.

Spencert231 wrote: You on the sauce again RTman10, the bike is in the title lol but I am curious as what is a side marker light?

Extract from Wikipedia re N American side markers:-
In the US, amber front and red rear side marker lamps and retroreflectors are required. The law initially required lights or retroreflectors on vehicles made after 1 January 1968. This was amended to require lights and retroreflectors on vehicles made after 1 January 1970.[39][/sup] These side-facing devices make the vehicle's presence, position and direction of travel clearly visible from oblique angles.[39][/sup] The lights are wired so as to illuminate whenever the vehicles' parking and taillamps are on, including when the headlamps are being used.[7][/sup] Front amber side markers in the United States may be wired so as to flash in synchronous phase or opposite-phase with the turn signals, but are not required to flash at all.[40][/sup] Side markers are permitted but not required on cars and light passenger vehicles outside the US and Canada.

Inside the headlight assembly, I am referring to the top outside bulbs.  One on each side.  The owners manual say these 2[194] bulbs remain on when the
key is turned on.  The manual lists them as side marker lights[I am guessing because you can see them from them in the headlight assembly, from the side view,
as opposed to the headlight bulbs.

The bulbs were not burning when the key is turned on, nor when the engine is started[like the headlights].  When I removed the existing bulb, it was blown
or defective.  As soon as I installed a new bulb, it began to burn[glow, light up], regardless of key position.

I wonder if the bike has any auxiliary items wired in as you seem to have a Canbus fault. Do you have any fault symbols showing on the dash when the ignition is in.

There is a  dash symbol showing a front bulb is out/defective.  There are a set of auxiliary lights mounted on the fork legs.  They have power, but they do not
light.

Couple of questions
How long have you had bike?
Has light out indicator always been on?
Did aux lights ever work?
This is a pre can bus bike so wiring should be simple
Can you tell how aux lights were wired
Do the have a switch
If I had to bet previous owner screwed up wiring
Last resort in manual I remember seeing something about parking lights, how to turn them on and off if I remember correctly
Electrical gremlins are the pits

I think all 1200RTs are canbus, hence things like warning symbols, but my best guess is someone in the last has caused the problem.

There were 3 leads attached to the positive battery cable.  I removed all 3, inserted a bulb, it did not light up, until I
turned on the ignition key, then it lit up.  Just like it is supposed to work.  If I touched 2 of the 3 leads to the hot
battery terminal, the side marker light would come and remain lit.  So, it had to be  in those 2 wires.  I also removed the
additional wiring that went to the auxiliary lights.

The 3rd additional wire was the fused feed to a GPS power supply.  Carefully checked all lights and engine and electrical
components to make sure all was as it should be.  Thankfully it was.

While I was at this, I added a battery tender disconnect if I need to use it.

Thanks.

Glad you're fixed.  There is a plug situated underneath the headlight, normally tied to frame part that is for a GPS. White plug sometimes with a black cover in it.