HARLEY SHOP TALK HARLEY SHOP TALK - BIKE FORUMS. I'm thinking something's loose and causing the ECM to lose power, or bad ground, or check charging system.
Starting Bike Dash Loses Power Fast
It is most lightly the stator or voltage regulator in your charging system not charging your battery while running, thus runs the battery dead. If your battery is completely drained, which usually is the sign when you have no lights and backfires and the battery has no juice left to support the spark plugs, and finally gives up, and thus won't take a jump. This is a common problem.
Battery needs to go on a charger and fully charged before you can conduct any electrical output test from the stator or voltage regulator. Just happened to me again this week. Hope this helps.Posted on Aug 18, 2010.
What It DoesWhat Does a Failure Look Like?AlternatorProvides power while the engine is running.Lights will typically dim, and the engine may die.BatteryProvides power necessary to start the vehicle, and powers accessories when the engine is off.The vehicle won't start at all, or will crank slowly. Driving a car with a dead battery can also damage the alternator.Fuses and fusible linksProvide a failsafe if something draws too much current.The engine may not start, or you may suddenly lose all electrical power while driving.Ignition coil and other ignition componentsProvides power to the spark plugs, and increases the voltage of the power provided to the spark plugs.The engine may not start, or it may die while you're driving. Electrical power will still be available, so your lights and radio will still function.Starter, starter solenoid, or relayPhysically rotates internal engine components until the process of internal combustion can take over.The engine won't start. A bad starter, solenoid, or relay won't cause a loss of electrical power.