lights pulsating

Discussion in 'Touring Models' started by Robert J, Sep 24, 2009.

  1. Robert J

    Robert J Guest

    The other evening I was coming back from and evening ride on 2003 Road King Classic when my headlight and running lights starting flasing from dim to bright at different times during the ride back. When I hit the interstate on a 5 mile stretch doing 70 they flashed six or seven times. Are we possibly talking voltage regulator or something else . Any suggestions are appreciated. Thanx in advance .
    Robert J

    NEWHD74FAN Experienced Member Retired Moderators

    Welcome Robert to the HDTimeline forum, where riders and enthusiasts share their ideas on how to service, troubleshoot and make their HD motorcycles perform. Make sure you check tabs near the top of the pagefor Self Help Tips & Search (using keywords).

    Based on the age of the machine and not knowing the circumstances in detail prior to the problem. I hope this simple schematic of the wiring will help...

    I would personally start with the the fuse connections and primary battery and ground wiring first...because they are easiest to access and inspect. Scrape and clean all electrical pins with pen knife or mating and removing them several times, making sure you have no receding contacts or evidence of corrosion. Then coat the contact pins with light film of (dielectric grease $9.95 at HD dealer). I would also pull the headlight relay fuses doing the same, making sure all connections are tight and corrosion resistant. I would then work my way from the headlight nacelle (divide and conquer), doing the same, checking bulb connector contacts and check wiring for chafing or cuts. Also check the ground wiring at BOTH ends, again scraping and coating with light film of dielectric grease. You might also have a bad relay, start the bike in neutral and using an insulated screwdriver handle, start tapping around the headlight nacelle and wiring harness connectors, including the headlight relay and fuses.
    Last edited: Sep 24, 2009
  3. Caper

    Caper Active Member

    Check for loose battery cables, had the same thing going on when I first got my 03, turned out to be a stainless steel spacer on the battery kept cutting into the post making the connection loose.
    If not at the battery keep moving foward it sounds like it's a loose connection or ground somewhere.