Engine Light. Low voltage.
I had a regulator go south on me some years back on my FXR.
I'd check the connections around the regulator. Then do a voltage output check as others have mentioned.
So I took it into the Harley dealer in Flagstaff. After they played with it for a while and listened to my story, the mechanic told me it's the regulator. He said he'd bet his next pay cheque on it. When I took it in, the voltage was up at normal levels, so they were going on my story since all diagnostics checked normal.
Problem was Flagstaff didn't have a regulator in stock, so I took the bike as is and there was NO CHARGE. How often does that happen at a Harley dealer?? So please give Flagstaff Harley some business, they're a great crew there.

I passed the next dealer in Las Cruces, and what another great dealership. They're huge. Took my story down, called Harley to verify warranty, pulled a reg off the shelf and popped it in. wwwhhheeewww. what a relief to get that problem behind me.
While I was there I asked the mechanic to take a look at that pesky squeaking belt. Turns out the rubber buffers in my rear sprocket were worn out. I sort of knew that but didn't know you could just replace them. So I told them to switch em out! They charged me for the work, but it was well worth the money, hundred bucks or so, that's nothing to get that problem behind me as well.
So, I'm a happy camper now, literally.




