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2010 Fatboy Lo Light problem

5K views 15 replies 6 participants last post by  ATK02 
#1 ·
Have beat myself silly trying to locate the problem. no rear lights, flashers, brakes or running light work and neither does the spedo backlight. Problem occurred suddenly. Also, front turn indicators flash at fast rate when activated. Have checked connection cable to rear lights, have traced all visible cables and no wear shows. All fuses are functional and not blowing, appears to only be getting power to one of the connectors in the cable plug going to rear. Any and all help would certainly be appreciated at this point. Bike is a 2010 Fatboy Lo.
Thanks
ATK02
 
#3 ·
While it's running..
Is the check engine light on?

Have you tried getting or done a code check?
Do you have a Harley repair manual?
 
#4 ·
Have beat myself silly trying to locate the problem. no rear lights, flashers, brakes or running light work and neither does the spedo backlight. Problem occurred suddenly. Also, front turn indicators flash at fast rate when activated. Have checked connection cable to rear lights, have traced all visible cables and no wear shows. All fuses are functional and not blowing, appears to only be getting power to one of the connectors in the cable plug going to rear. Any and all help would certainly be appreciated at this point. Bike is a 2010 Fatboy Lo.
Thanks
ATK02
Those are two different light circuits. Test power at the fuses with a test light or meter, ignition on.
Do the front directionals come on or just the indicators flash fast ?
 
#5 · (Edited)
Ok, let me answer a few of these
Yes I have the factory manual
No I haven't done a code check
No, no bulbs burned out
Check engine indicator is not on with engine running
Yes all fuses have been checked as well as relays and everything is good.
Yes the front signals as well as indicators on the speedo all appear as normal

And thanks in advance to all who have responded!!!!!

One new symptom just found. When turn signals are turned on, left or right, the turn indicator flashes at normal rate for FOUR flashes then goes into double rate flashing.
 
#6 ·
For those that have helped, I had to pull the bags and tire to find part of the problem, skinned wires. Symptoms have changed drastically with repair. Now rear flashers both sides work. Rear running light works. Front left flasher works but right side has a barely discernable dimming rather than a flash. Also no brake lights off hand or foot controls. When the security system sets all four blinkers light nice and bright to indicate going into secure mode.
Code check returns two codes b1121 and b1122. That indicates a problem on both sides but the left works properly on front and both work properly on rear.

One other thing that is a bit confusing. When in diagnostics mode the backlight on the Speedo works but when in run mode it does not come on???

Am I just chasing ghosts or is there something simple I'm missing??
Thanks Again all
 
#8 ·
Front left flasher works but right side has a barely discernable dimming rather than a flash.
Both front and rear flashers on the right side are powered by the same circuit, if the front bulb only dims, then the rear bulb will do the same.

I think you have one burned out running light up front on the left side, so you are seeing the left side go completly out when flashing, but the right side has a good running lamp, so it looks like it is only dimming instead of flashing (which is exactly what it should do).
 
#9 ·
Both front running lights are functioning normally. All lighs front and rear are led's. And yes left side goes completely out on the flash but the right just barely shows a slight dimming. Rear signals function normally. And no brake lights
 
#13 ·
It would make no sense to use two load equalizers on the same side, each side is a single circuit...

Do you mean one equalizer for right, and one for left?

And now the 64 dollar question...is there an aftermarket electronic turn signal/brake light controller installed on the bike?
 
#16 ·
Well this particular scooter was my brothers and he left it to me when he passed. Relative to this particular issue would be the Kurakin light controller and the led lights front rear and stop/running. When I brought it home all was fully functional but before long the controller assembly overheated and smoked. I pulled it and used the LED light only provided interface harness which has the two load connectors on it. Once that change was made all worked without problem for over a year. As this is a spare bike I probably only put 1500 miles on it after remod. Apparently on trip home from a south texas run I bottomed out and skinned some wires in the rear wire harness. Found that and corrected it all today which returned most of the light functions with exception of what I've noted.
 
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