Aux lights troubleshooting

Discussion in 'GS Boxers' started by Thinc2, Apr 30, 2012.

  1. Thinc2

    Thinc2 Paciugo

    Joined:
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    Location:
    Seattle
    2002 1150 GS. Recently had some work done on my bike, including having the clutch and alternator belt replaced. After I got home a full day's riding from where the work was done I noticed my fog lights were not working. I asked the fellow who did the work, and he said the only thing he did was to disconnect the battery. this is somebody who absolutely knows what he's doing and I trust implicitly.

    I checked to make sure the lights hadn't burned out, by removing one of them and testing it from an alternate battery. It checked out fine.

    I then noticed that both the white wire (power) and the black (ground), had power going to them. Both were showing 10.95 V at the light.

    Tracing the wires they both run straight into the bottom of the fuse box. I do not see any relays or fuses outside of the fuse box.

    Since I have been switching the ignition on and off to test the lights while I was troubleshooting, I decided to hook up the battery tender, only to find that this connection is not working either. I have not had a chance to do further troubleshooting to see if the two are related, or if I am getting power to the auxiliary plug.

    I have checked all the fuses in the fuse box, including #3 which should be for the aux plug and the RID. The RID is working fine. All other lights and electrical devices on the bike are functioning properly.

    I had a spare relay, and tried replacing all the standard relays, with no effect. There are two larger, what I assume to be relays, in the fuse box, that I do not know how to test. I can take a picture if required.

    I then hooked up the white wire to the light, and grounded the light manually to the engine frame. The light came on but I got a screeching or whining noise from the fuse box.???

    Now I need some help :norton

    Does this sound like a problem with arelay? I am leaning this way since both my lights are out?

    Could a failed relay cause my ground wire to be powered?

    How do I get at the wires under the fuse box to understand what is going on in there? Right now I cannot see where the wires from the lights go to in the fuse box.

    how do I test the auxiliary socket to determine if the two issues are related?

    Really appreciate any advice on how to troubleshoot this.
    #1
  2. Taz34

    Taz34 n00b

    Joined:
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    Location:
    South of France
    Hi Thinc2,
    Do you have the original BMW foglights ? or OEMs ?
    I did install BMW original Foglights and could help trouble check your issue.
    Have you checked if the 12V Power connector has been disconnected ?
    Check here, behind the Engine starter.

    [​IMG]

    Uploaded with ImageShack.us

    or check for relay device located behind bike's dashboard :
    [​IMG]

    Uploaded with ImageShack.us

    Send me a PM for a call, you are in Europe like me, could help also by phone.
    Taz34
    #2
  3. Thinc2

    Thinc2 Paciugo

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    Thanks Taz :1drink the issue with the auxiliary plug has been solved. It turns out that my battery tender had developed a loose wire inside the BMW plug. The good news is that as part of the troubleshooting process I now have beautifully clean connections in my auxiliary plug :D

    The main issue with the fog lights remains. The lights are aftermarket, not BMW. I can find no relays or fuses along the wiring between the lights and where they enter underneath the fuse box. I cannot see enough into the fuse box from the top in order to see what wires they are connected to.

    The questions I have are:

    Are the symptoms I described likely to be the cause of a faulty relay?

    If that is the case, why am I not experiencing any other electrical problems on the bike?

    What other causes could make the ground wire be showing nearly 11 V at the lights?

    How do I access the underside of the fuse box to be able to see what is happening and how the wires from the fog lights are connected?

    I have tested all the relays except the two large black ones on the top left below (to the left of the jumper wire). I am not sure what these do, but again if there were a fault, I assume I would have issues other than just my fog lights, correct?

    [​IMG]

    Thanks.
    #3
  4. Lensgrinder

    Lensgrinder Long timer

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    I would check the wiring harness connections comming from the rear of your motorbike.
    To replace the clutch, the rear sub frame must be removed or rotated up out of the way to remove the transmission.
    You may want to ask your mechanic which method he used.

    Odds are that while manipulating the rear sub frame out of the way a wire came disconnected or broke,
    and the trouble stems from that.
    Assuming everything work prior to the work just performed.
    Good Luck,
    Richard
    #4
  5. Thinc2

    Thinc2 Paciugo

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    Thanks Richard. Can you give me a little more detail what I am looking for – is there wiring other than for the rear lights in the rear subframe?

    Also, if the wires for the fog lights are going directly into the fuse box, how would they be impacted by wires behind the fuse box - just trying to understand what to look for.

    Finally, remember that when I used the regular powered wire and grounded the light manually, I got a whining or screeching noise out of the fuse box. With that symptom also fit with your suggestion?

    Really appreciate any help,

    Thanks
    #5
  6. Lensgrinder

    Lensgrinder Long timer

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    Mostly you would be looking at any wire or harness that had to be disconnected to move the sub frame out of the way.
    Sorry I can't be more specific as I haven't worked on a pre-Canbus bike since I sold my '95 R1100GS four years ago.

    I'm betting it's a connection your mechanic foregot to plug back in or plugged in to the wrong connector when he rejoined the rear sub frame.

    I would definetly give the mechanic a call, me might remember something he did or didn't do.
    Richard
    #6
  7. Thinc2

    Thinc2 Paciugo

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    But in this case I would have something else on the bike not working - which is not the case? (I have asked him btw)
    #7
  8. Thinc2

    Thinc2 Paciugo

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    #8