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Does anyone know if I can wire one fog light to the other?

Discussion in 'E39 (1997-2003)' started by ronfrohock, Mar 27, 2010.

    • Member

    ronfrohock

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    I suspect I fried the power to my drivers side fog light coming out of the LKM.

    My passenger fog light is working.

    I wonder if I could pull power from the passinger side to splice into the drivers side without causing any problems.

    Basically, take power from the working circuit - power both fog lights from one side of the car / harness......

    Does anyone have access to the schematic?

    Its not likley that there is a single fuse for one fog light vs. the other - correct?

    Any ideas?

    Thanks
    - Ron
    • Member

    CRKrieger

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    Yeah. Why not fix the problem instead of patching around it?
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    ronfrohock

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    The LKM is on the fritz

    Its either going to cost me many hndreds of dollors for a new LKM or a few hundred to get it repaired.
    If I can simply ard wire one to the other it will be free.

    Can anyone tell me if they are both on the same feed?
    Thanks
    - Ron
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    Zeichen311

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    ...until it causes other problems. Just because they are on the same feed (even if they are) does not mean the wire gauge of the lead to the right-side lamp is sufficient to carry the load of both lamps. At best, you blow a fuse immediately. At worst, you have an electrical fire. In between lie all manner of potential problems, such as your already-dicey LKM becoming confused by the apparent twice-normal current drain of the starboard lamp.

    Electrical hack jobs--and what you are planning is a hack job, no offense--often lead to tears. It's your car and your money, but this is not a good plan.
    • Member

    ronfrohock

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    Understood.....

    You have valid points. I appreciate your advise and agree with you.
    I spoke with the dealer and they are giving me the schematic to the pinouts on the LCM.
    I will be able to trace the circuit easily with this information.
    I hope its a component that is commonly available.
    Thanks again.
    - Ron
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    CRKrieger

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    Glad to hear this. We've seen cars literally burn because of LKM problems. I'd hate to see yours do that because I actually like E39s. Hopefully, when you're done, you'll have something to add back to this forum for others with similar problems. Remember to take lots of pictures!
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    nd4spdlsc

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    The LKM actually adjusts voltage to prevent spikes, etc. By wiring an extra bulb in series to one of the outputs you alter the circuit greatly. I am not sure if the LKM can accomodate the extra load on one pinout.
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    102929

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    Warning message?

    I tend to agree with the others about not doing a hack job for the following reasons

    - may affect the power transistor for the other lamp over time
    - wiring could overheat. If it does and causes a fire then the insurance company will investigate and any improper mod means your insurance is not valid
    - next owner and any maintenance person has a very difficult time of doing maintenance when things are modified (especially if not documented)

    As well - The LCM monitors the system current to give you a warning of a failed (or pending) bulb circuit. Adding the additional bulb may trigger the warning message.

    Cheers
    Jim Cash

    BMW Auction Prices guest

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    If you must do a "Hack" J.O.B. and are worried about the amps you can always buy LED lights that consume 1/10th the amps now and are just about as bright. No worries from the amps in this case.
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    bcweir

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    Not from the amps, the VOLTAGE.

    You're going to have to check the voltages on the LED's. They are NOT all the same voltage.

    Applying 12 volts to 5 or 7 volt LED's (without the appropriate resistors) will kill them faster than you can say snap crackle pop.
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    CRKrieger

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    You mean these things?

    [IMG]

    "Ultra Bright White Colour 13 SMDs LED Bulbs H1 13w, Ideal for Modifying the Bulbs of Your Lovely Car"

    I have some reservations about their effectiveness but, since the vast majority of BMW drivers who use their fog lamps use them primarily for posing, not for fog, I suppose they'd be just fine for Your Lovely Car ...
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    tdubyu

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    Intermittently Out High Beam/DRL Light

    Has anyone experienced their Hi-Beam/DRL left or right intermittently going out and coming back on by themselves, more with the right ? I can disconnect the bulb harness and reconnect it with the light and ignition switches in the on position they would re-energize themselves. At first, I thought I had bad bulbs and replaced them, but after several tests I found what maybe the culprit cause is, flashing them.

    Thanks for your input.
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    granthr

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    I admit it, I am a fog light poser. I fully expect CR to bust out my fogs when he sees me! :D

    UsedBits guest

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    I thought I was the only one disappointed with the performance of the e39 fog light.
    • Member

    CRKrieger

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    I'm not destructive. I just roll my eyes and feel embarrassed for you. See the fogs on the picture of my car? They're no longer there. One broke a mount and the other was superfluous. The holes look much cooler.

    UsedBits guest

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    So, is something available with which to improve the fog lights' performance? I see on eBay, for example, kits to convert them to HID. Does this help? Or is this just to match them with the HID headlights?

    If, for example, the LED lights produce the same light output at 1/10 the power consumption, then would LEDs 10 times as powerful produce a 'better' fog 'beam'? (I'm assuming that 10 times brighter will look twice as bright.)
    • Member

    CRKrieger

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    You can also see Vortec Turbonators on ebay ...
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    granthr

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    Thanks CR I was looking for a source for them!!!! My local dealer wasn't carrying them anymore for some reason. Something about the fuel pump failing so something. :D

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