battery cuts out inexplicably


New Member
My fairly new battery cuts out inexplicably. It has a charge but cuts off. I notice, even with on/off button to off, it generates juice for the lights. Sometimes, after I let it sit off a bit, it turns back on when I switch it on. Other times, not. My charger is a bit goofy and may be involved. Any advice?

Angela M.

Staff member
Hey Byron! Sorry to hear you're having trouble with your battery. Can you give us a little more info on the kind of battery you have? How long have you had it and why do you think your charger could be an issue?


New Member
Thanks, Angela. The battery is 36 Volt, 11 Amp hour Sanyo lithium ion: UM1006F,
and the charger is
High Power Li-ion, Taiwan
Model: HP8204L3
Serial Number: 1011646
Input 115/230 VAC, 60/50 Hz 2.4/1/3A
Output: 42VDC/4A

The battery charger sometimes flashes red alongside of a red on light. The fan rattles and the charger gets sort of hot. Sometimes after seeing the red flashing light I turn it off, wait, and when I turn it on again, it goes to standard charging (solid orange light). It could then go to flashing orange (trickle charge) before going to flashing red.

I haven't yet downloaded the service manual; the company offering it would take over my browser, which I fear letting them do. Other sources for the service manual would be appreciated.

Suggestions on a replacement charger would also be welcome. I suspect one with less amps than 4 would be safer for the battery system. I also have no way of knowing when the battery is fully charged other than at end of trickle charge time.

Is there a battery management system on board that could be monitored and/or repaired?


New Member
Well, the charger finally broke. The fuse looks OK, but no power goes through it.

Does anyone have a recommendation on a replacement for my HP 8204 L3? It puts out 42 volts (my bike is 36 volts) at 4 amps (I suspect less amps would be safer for the battery). Any recommendations on specific ones or reliable companies would be appreciated.