CANBus (bulb out question)

Discussion in 'Parallel Universe' started by battlecattle, Jan 24, 2013.

  1. battlecattle

    battlecattle Been here awhile

    Joined:
    Aug 6, 2010
    Oddometer:
    271
    Location:
    Tail of the Dragon
    Simple question but I cannot seem to find any information.

    I am assuming that the CANBus system runs off Amps and the headlight has to draw so much current for the "bulb out" light to not turn on. Does anyone know what that magic value is?

    I am making a low amp headlight for an upcoming trip and need every amp possible. I have already tried an LED bulb replacement which throws a "bulb out" light and eventually CANBus turns it off. That LED bulb drew .5amps and the stock draws 4.8amps.

    Any information about this would be helpful, even if it is just how to turn off the "bulb out" so the CANBus doesn't shut it off.

    Thanks
    #1
  2. Bayner

    Bayner Long timer

    Joined:
    Mar 27, 2008
    Oddometer:
    1,727
    Location:
    Penticton, BC
    It may be easier to wire it into something yourself than fight with the computer.
    #2
  3. battlecattle

    battlecattle Been here awhile

    Joined:
    Aug 6, 2010
    Oddometer:
    271
    Location:
    Tail of the Dragon
    Complete true but I also don't want to buy 2 1.2amp lights and need 3amp to "fool" the computer.
    #3
  4. Moto Mikey

    Moto Mikey Been here awhile

    Joined:
    Jun 28, 2008
    Oddometer:
    456
    Location:
    Charlottesville, VA
    I recall reading on here that you can have the canbus ignore the low voltage/amperage from bulbs via a reflash.
    #4
  5. Reaver

    Reaver Outta Here

    Joined:
    Aug 7, 2008
    Oddometer:
    8,139
    Location:
    Zona Sur Costa Rica
    Not exactly. You can tell the ZFE that you installed LED turn signals so it won't give you a bulb warning but I've never seen anything on the BMW computer for headlight options. I was a BMW Tech for three yrs so I've done that but I'm not saying I know everything. :D
    #5
  6. Moto Mikey

    Moto Mikey Been here awhile

    Joined:
    Jun 28, 2008
    Oddometer:
    456
    Location:
    Charlottesville, VA
    Humm.. yeah, maybe that's what I read (and I think you might have posted it :D )
    #6
  7. vtbob

    vtbob wanderer

    Joined:
    Jun 20, 2009
    Oddometer:
    653
    Location:
    Western Vermont
    the can bus is a data network that has a micro processor/network/data acquisition function on each node. On the headlight node it measures voltage/current to detect a burnt out bulb. I do not know the settings that make this function works. I suspect but do not know there are the same settings in the directional or tail light nodes...so quite low.

    I suspect that you will have no problem with a "low amp" head lamp. try it you can do no harm in just changing the bulb.

    I think the can bus will work with this just fine
    #7
  8. TowPro

    TowPro Lets ride

    Joined:
    Aug 21, 2009
    Oddometer:
    3,474
    Location:
    Compass PA
    I know it's OK with my 35W HID's.

    P=IxE 35w / 12V = 2.91A

    Not sure if your trying to save power, or create more light.

    the cheep 35W hid's really work great. I bought VVME.com.

    If your trying to save power, realize the stator produces 100% output all the time, what you don't use is shunted to ground through the voltage regulator.
    #8
  9. battlecattle

    battlecattle Been here awhile

    Joined:
    Aug 6, 2010
    Oddometer:
    271
    Location:
    Tail of the Dragon
    I am trying to cut as much power as possible. 2.9amps is great but if I can get that to 2.5 or even 2, that is a free amp to use elsewhere. LED headlight and a dimmer is a perfect way to cut my 4.8amp headlight to as low as computer possible and use that elsewhere.

    Just some quick info I have compiled

    My heated jacket and gloves on high draw 9.2 Amps
    Stock headlight at the same time draw 4.8 amps
    bringing my voltage down to 12.9v

    so I am trying to bring everything under 13-14amps so I am not discharging my battery.

    edit:

    http://stores.intuitwebsites.com/hstrial-QualiRegResou/-strse-61/M61-LED-Light/Detail.bok

    this is what I am wanting .6amps!!

    or http://stores.intuitwebsites.com/hstrial-QualiRegResou/-strse-62/M62-LED-Light/Detail.bok

    @ 1.2amps
    #9
  10. PatrickM

    PatrickM Been here awhile

    Joined:
    May 6, 2012
    Oddometer:
    410
    Location:
    Zephyr Cove, NV
    A 55W H3 generates about 1500 lumens, so plan accordingly.
    #10
  11. TowPro

    TowPro Lets ride

    Joined:
    Aug 21, 2009
    Oddometer:
    3,474
    Location:
    Compass PA
    Don't this bike have a 400W stator? 400w / 12V = 33.3 Amp. Maybe your real problem is you stator is going bad?
    Very common thread on here is http://www.advrider.com/forums/showthread.php?t=706033
    #11
  12. sorebutt

    sorebutt Long timer

    Joined:
    Jun 26, 2008
    Oddometer:
    2,328
    Location:
    Lewiston,ID
    I use a pulse control for my heated jacket. I never have it on full because it is too hot. I watch my volt meter and it drops to 12 volt when the controller turns on the jacket and then jumps back up to 13-14 when it shuts off. It would run down the battery on high, but it would have to be very cold to run it on anything at more than half power.
    #12
  13. lunaticTR

    lunaticTR Adventurer

    Joined:
    Oct 3, 2009
    Oddometer:
    99
    Location:
    Ankara, Türkiye
    I use heated jacket and pants and heated hand grips. When everything is on full power, It goes down to 13.8V from 14.1V @2Krpm and over. At idle it is a different story. And if I turn on the long beam at the same time, it goes down to 13.3V if I recollect correctly. Are you talking about voltage drop when you are at idle or it happens when you are moving? If it happens when you are moving you should get your charging system checked. If you are close to 40K miles you are at risk of a burnt alternator. :(
    #13
  14. battlecattle

    battlecattle Been here awhile

    Joined:
    Aug 6, 2010
    Oddometer:
    271
    Location:
    Tail of the Dragon
    Yes the stator puts out 33amps before the bike is running. Unfortunately all the computers and electronic stuff draws between about 13-15amps. Now that leaves right around 15-18amps. My heated jacket draws 7.4amps on high and with my heated gloves plugged in 9.2amps now lets add 4.8amps for the highbeam. That brings the total to 14amps. No room for heated pants, heated grips, AUX lights, or even cell charging.

    I would also error on the side of caution because it is your battery and you don't want to kill it. That is why I wan't to get down to 13-14amps max. Completely turning off my headlight would give me 9.6amps which is over half of my current max amperes. Finding a Low beam headlight under 1amp and a highbeam at 2.4amps still gives me a net gain of 6.2amps. With that extra boost in power I virtually eliminate the chance of overdrawing my stator even at idle.

    I based everything off idle, because that is where it is important to me. Stopped in traffic is when you are going to want that heated jacket, pants, and gloves.

    EDIT:

    I also found that the Bulb out light does not come on at a draw of .8amps, sometimes I see .7amps on my meter but i don't trust it since it is not sustained.
    #14