I was riding with the wife and both the battery and engine light came on at once. I stopped at a service station and checked over a few things but it was running fine. I filled it up with fuel and the lights came back on, but went off about 5 minutes later on the way to get the bike home. I took it on a few short rides today and the check engine light only comes on right after its started but goes off in about 10 seconds, didn't do this before either. Just to let you know, I swaped out the bars and cables a few weeks back and added wire extensions, etc. I have been riding for 3 weeks with no problems till now. I took the bike to the carwash the night before the engine and battery lights came on, so that could be contributing...but I doubt it. The bike only has 4500 kms on it, so this sort of worries me. Help me out here guys, I'm missing out on a weekend trip this weekend already because I'm afraid to ride the bike far in it's current state.

 

The engine and battery light will come on when you alternator is not charging/running the electrical system of the bike and are running on battery power alone.

Since this is intermittent, it sounds like you have some sort of loose connection or possibly a broken wire that breaks and makes with vibration or a specific condition/movement... I would SERIOUSLY focus on the areas you modified for the handlebar changeout that you did.

Past that, and not knowing the model/year of you bike (or your mechanical familiarity with Harleys) try the following... check all wiring and connections starting with the wires that come out of the front/left portion of the engine crankcase (those are the wires from the stator portion of the alternator) and follow them to the voltage regulator (the squarish box on the front down tubes of the frame behind the front wheel), and check all those wires and plug connections.

If you are skilled in the use of an electrical multi-meter and reading electrical schematics/diagrams you may have to take ohms readings to trace the circuits to see if they are intact, not shorted to ground, as well as take voltage readings to see if your alternator and voltage regulator are actually putting out the proper voltages.

In a nutshell, the output of the alternator is 3-phase AC current which goes into the voltage regulator, which in turn rectifies the AC current into DC current that runs all the electrical demands of the bike and trickle charges the battery while the engine is running... if anything interrupts that process the engine and battery light will come on.

The BEST THING you can do for yourself is get the proper service manual for your bike. You can even do a fault code diagnostic "flash code" with the proper combination of key turns, and switch activations with the info in the service manual. If you don't think you can tackle it, you might be better off with going to the dealership and let them have a go at it.

Hope that helps!

 

Car washes and bikes don't mix. Water and bikes don't mix. Take the seat off and let it sit in the sun for a day to dry things out, maybe use an air hose or leaf blower to assist.

 

Wow this one might be a bit over my head. I was really hoping I didn't bugger anything up with the electrical because it will be a full day affair to take everything apart and check the wires...not to mention I have no idea how to even check them. Crap....

 

Both those lights came on while I was riding once. I keep going then noticed the lights wernt working... then the motor started running like crap... then it stoped running.
After I got it home with a pick up truck I found this:



Thats the battery side of the voltatge regulator. The service manual instructed me to examine the connector plugs & pins and clean them as needed. I inserted a small round file into the female pin for a little cleaning and and pulled out the round part of the pin which had broken off from the crimp part of the pin.

This prevented the charging of the battery.

 

I used the manual to do a diagnostic check and the codes that came back were that there was low voltage and the other was that the clutch was grounded, or something like that. I am completely lost with this. I do not have the tool they said I need to hook up to the different connections to test them. This is probably something the stealer could fix in 10 minutes but will charge me $500. Awesome.

 

when my nightster did this last year it ended up being the regulator, low side voltage was working intermittently and when the lights came on the bike would only charge above 2500rpm.
if i ran 70 on the highway it would charge fine, took 3 tries but i finally got it to do it
while i was at the dealer and they brought it right in a tested it and found the problem, under warranty but it ruined my 4th of July plans last year

 

I'm having the same issue right now after riding my bike and it dying in a huge rainstorm last week, I've dried out all the terminals to/from pc3 and reloaded a map, swapped plugs an checked fluids for water mixture. Ran ok for short test run then got on it to go to work today , two blocks away it staring running irratic an got a very disturbing whirring metal sound coming from the motor, which area im not sure but I know it not the cylinders I'm thinking within the primary. Both battery and engine lights came on as well. Tommorow is going to be a fun day of chasing the ghost in the machine!

 

Car washes and bikes don't mix. Water and bikes don't mix.

 

Okay having the same issue with the Battery & Engine light mine came on while riding in the rain. And I too also have the Engine light that eventually goes out. I will be checking loose/dirty connections also. I'll try to report back what I find. With close to 80,000 miles on my 06 Electra Glide and riding in all kinds of weather I will disagree with the car wash/water & bikes don't mix statement, unless your riding in it knee deep.