speedometer and ABS acting strange

Discussion in 'Dakar champion (950/990)' started by maxtotow, Apr 24, 2014.

  1. maxtotow

    maxtotow Adventurer

    Joined:
    Oct 16, 2013
    Oddometer:
    79
    Location:
    Lafayette, LA
    My 2012 990 has started doing something different with the speedo and ABS arming light. Normally the light goes off at about 3mph or basically as soon as the bike is rolling. Now the speedo does not register speed until about 8 mph and of course the ABS light stays on until the speed comes to life. It only seems to do this after the bike has sat for a few hours or overnight. If I see the behavior and after it starts working, I then stop and turn off the key, the next cycle it works fine like always before at 3 mph and the speedo comes to life immediately upon rolling. the sensor has not moved and i don't see any binding wires.
    >>>> More to add to this. The problem got worse and i rode to work with no speedo the whole way. then I realized I had no blinkers, no horn, no tail lights, no brakelights. So i pulled and reset fuses and it started working again. then this morning the same thing, but no matter how many fuses i reset the lights and stuff did not come on. So, i just took off riding and about a tenth of a mile, poof everything comes all like nothing was wrong. SO, I think it is a relay somewhere that is not activating. Could it be the light relay? I am not sure but i think the relays are under the dash behind the headlight.
    <<<<
    I have of course searched here and read other threads about ABS and speedo failures. and I have seen a few others with some similar problems.
    the suggestions have also included the rectifier/regulator, but I don't understand how that would cause this strange stuff.
    Any one else see this? The bike has about 8000 miles but the odometer only shows 2100 miles. I posted about one other issue on the bike related to the temp display bars on the dash. i never did get the dash display resolved, but the bike seems to run fine in regards to temperature.http://www.advrider.com/forums/showthread.php?t=951441
    thanks for any input. I am always looking in the "orange crush" for more knowledge to gain about this great bike. It is just fun to ride.
    #1
  2. JoeMongo

    JoeMongo ¿Por dónde? Supporter

    Joined:
    Dec 9, 2004
    Oddometer:
    1,140
    Location:
    SF Bay Area, not exactly dirt moto heaven
    You might try disconnecting the main ABS wire harness connector, and re-seating it. The ABS pulse ring signal goes through the ABS electronical gismo, where it gets the number of pulses divided by 8 and the pulse magnitude (voltage) massaged, so I suspect that your source of complementary problems must be back there.

    Unfortunately, bad connections rarely go away in a predictable, repeatable manner, like you describe, so that probably won't solve your problem. Can't hurt though!

    Then I guess you could start shotgun troubleshooting (change parts, gets expensive quick). I'd still start with the front wheel ABS sensor.
    #2
  3. gefr

    gefr Life is a trip

    Joined:
    Nov 26, 2005
    Oddometer:
    5,089
    Location:
    East Med, Greece
    I don't know anything about your specific problems, but as a general precaution I would suggest you check your R/R output. They are known to trigger strange behaviour to the speedo. R/Rs are affected from high temperature.
    Hope that helps.
    Cheers
    #3
  4. Renierd

    Renierd Renierd

    Joined:
    Mar 5, 2013
    Oddometer:
    50
    Check your regulator/rectifier, had the same issue with my 08, replaced the rectifier, and haven't had issues again. Does your bike battle to start after a week or so of not riding? Check your battery as well, because the failed regulator stuffs it up, overcharging.


    Sent from my iPad using Tapatalk
    #4
  5. Doktor O.

    Doktor O. Been here awhile

    Joined:
    Mar 27, 2011
    Oddometer:
    821
    Location:
    TN
    Check the R/R for sure. They are absolute steaming piles o' shit with non waterproof connectors. It's not if but when. Put a MOSFET on it if that is what it turns out to be. There are a few how to threads on that floating around.
    #5
  6. maxtotow

    maxtotow Adventurer

    Joined:
    Oct 16, 2013
    Oddometer:
    79
    Location:
    Lafayette, LA
    ok so maybe the rectifier is doing something weird to the relays? what is the best way to test this? I have checked the charge voltage and it seems ok, something like 13.5 volts, but i need to confirm that.
    I edited the original post because i learned of more issues.
    thanks
    #6