I have a 06 Ultra Classic. The voltage gage drops 14VDC to 10 VDC and the battery and check engine light comes on. This may last for several miles and then it returns to 14 VDC and the check engine and battery lights go off. This will happen several times in a 50 mile distance. What would cause this and what would be some things I could check.

 

is this a repeat thread from last night?

Rick if you lost your thread, just click on your username and it'll allow you to "find all posts"

of you can use the search function

Mike

 

I would check the connections and if that don't work you might want to have a load test done on the battery.

 

i just went through the same thing with my 05 road glide with a little over 61,000 miles. compensator nut was loose and that allowed all the splines to be torn out of the rotor. if the rotor is not turning at engine rpm your charging system is not charging. mabye you are lucky and dont have the same problem. test your charging system and battery. could be bad battery,bad stator, bad voltage regulater, bad rotor. good luck finding the problem

 

I checked all connections on the voltage regulator.
I checked the battery with a calibrated fluke meter 12.79 VDC
I checked the battery with engine at ideal 13.87 VDC
I checked the battery ground to several points on the frame and engine.
I unplugged the stator from the voltage regulator check across all 3 leads and each to ground, nothing was shorted.
I checked the AC output of the stator, with the engine at ideal 20-25 VAC, at 2000 rpms 40-48 VAC.

I will be riding my bike to work tomorrow to see if the problem reoccurs, 45 miles one way.

 

You need to carry your voltmeter with you and do these voltage checks when the check engine and battery lights are on and the voltmeter drops to 10 volts.

If the lights aren't on and the dash gauge reads 14 volts, you're not going to find anything wrong. Intermittent problems can hard to find. Good Luck.

 

Sure sounds like a faulty connector "somewhere". most likly a ground. i know you have checked the battery ground but if it is intermittant it may not show up at that point in time. Thus, 1st thing i would do is to unbolt the battery ground, clean and reconnect. If that doesn't do it would go through all the grounds

 

Same thing happened to my 2012 Ultra. Recheck and clean all your grounds.
I had two ground wires loose from the factory.

 

Had the exact intermittent voltage issue, although not as frequent as you described - just had the voltage regulator changed under warranty... the system was charging the bike, but there was some back-feed on the regular, per the HD tech.

 

I finally have my bike back on the road. I replaced the voltage regulator and it holds steady at 14 plus on the volts gage.