Salutations from Myrtle Beach, SC

[E-Wishbone]

New to forum, need help. I have 2 e-bikes that won't take a charge. Chargers flash green, but won't charge batteries. Both batteries need to be charged so chargers should display red light. I replaced 5A fuse internal on one and it took a charge, but now charger is flashing green again. I have tried different chargers and same results.
Any advice would be helpful. Thanks

 

[Smaug]

Welcome to the forum, from SE Wisconsin.

What is the make & model of the bikes?

 

[E-Wishbone]

Make and model; One is a chrome-moly Uni-vega MTB w/ 1000W DD kit, 48V, 20AH Lipo, the other is Jetson 48V 12" wheels.

 

[Smaug]

If you're trying to charge outdoors, the first thing I would try is to bring them in and let them warm up for a couple hours, then plug them in again.

If that doesn't work, check the output of the charger with a voltmeter.

If the charger is putting out and the batteries are warm enough to charge, then the batteries have likely developed a fault.

 

[E-Wishbone]

Thanks Jeremy; it`s pretty warm in SC unlike NH where I came from or Wizconsin. I have a new charger coming ;hope that will work.

 

[Smaug]

Another thing to consider is how warm the batteries were when you tried to charge them. The BMS (battery management system) that is built into the battery packs will prevent charging if the cells are too warm from use. If there's a chance of this, let them cool for an hour or so before plugging them in to charge.

An example: A woman in my club is heavy-set and rides an electric fatbike. She was riding with us roadies in a hilly area, not doing a lot of work. At one point, her bike cut out. Probably the motor controller overheated from her throttling up the hills at 20 mph. It could have also been the battery, due to the BMS stepping in to keep the cells from overheating. She panicked and started troubleshooting, but the bike worked fine again after it had sat for 20 minutes or so.