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Security light comes on while driving

  • scooter
    scooter
    4 years ago
    Hi guys,
    I have a 2014 fatbob with 20k on the clock.

    My security light is coming on randomly while I’m driving at 100kms.

    I have replaced the fob battery about 1 month ago.

    How often do you guys change the fob batteries?

    Is there something else I should be looking at.

    Regards,
    Scooter.
  • Ken in Cairns
    Ken in Cairns
    4 years ago
    The fault is with the front master cylinder not returning fully out, and this causes the brake light to come on when the brake lever is forces back by the wind at speed.
    Go and see how long it takes your brake light to go off when you operate the front brake.

    I had exactly the same issue with my 2012 FatBob, mine took a good 5 to 7 seconds to go out when the lever was released.
    Rebuilt front master and all 3 of the calipers and new fluid front and rear.
    Wasn't cheap as the caliper kits are bloody expensive as HD don't 
     do a seal kit.
    I think the bill was around 700.

    You need to change the brake fluid at least every two years and one yearly is better, I got told do it every 6 months because of the high humidity up this way.

    One of my jobs when I get home actually.
    HD say you need to bring it in because to operate the ABS pump you have to have it hooked up to the HD technician 2.
    I am just going to bleed and top up etc till I run through 2/3 s of a bottle in the front and the last 1/3 for the rear.
    This might not change out a little in the ABS pump but if 90 % is new it will reduce the overall water in the system.
    I can't afford 300 to just get them to do it this time.

    You can remove the brake lever and build up the bit that contacts the stop light switch, only needs to be a mm or so, I used some metal putty but a few layers of duc tape may do it.
    Not a cure for the master cylinder issue, and that needs to be sorted, but will stop your brake light coming on wjen you are at Hwy speeds.
    Good Luck
    Ken

  • steelo
    steelo
    4 years ago
    The security light KIC?
  • Ken in Cairns
    Ken in Cairns
    4 years ago
    Yep red led on the speedo, one that flashes when the alarm is armed.
    I changed the fob batteries, still came on now and then.
    I asked one day at the stealer and did the test in thier carpark.
    Booked it in next time I came home.
    Never has happened since.

  • scooter
    scooter
    4 years ago
    Thanks ken
  • Big Steve
    Big Steve
    4 years ago
    As Ken said its your front MC.
    I have 80,000km on my 2014 fat bob.

    it Started doing it at about 20k. After a flush of the brake system it was good for another 20 but eventually we replaced it and its been good now for probably 40k?

    Aparently the Moco is on like the 5th revision for the mc design used on fat bobs.
  • Timmy
    Timmy
    4 years ago
    Have you checked your stored error codes on your bikes computer?  That could give you a code to point you in the right direction too. 
    If you are unsure how to check these here is a link:
    http://www.motorcycletireco.com/motorcycle-service/harley-davidson-repair/harley-fault-codes/

     

  • JFE
    JFE
    4 years ago
    Had my Fat Bob's front master cylinder replaced under warranty in 2015 but that was more to with a vibration through the front. 
    Before then I had the red light issue once but that was caused by travelling too fast for too long which depressed the front brake lever just enough to have the brake light on for too long (hence the warning light). 
    Slowed down, light went out. No probs since ... but better check when last changed brake fluids. 
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