Charger switching off too early? Any ideas on a fix - replace capacitors or diodes?


New member
Local time
7:51 AM
Apr 14, 2022
Hi, I have a 52V 20Ah battery that I charge at home and at work - i.e. two separate chargers - same brand and model - this is because my commute is far and one battery charge doesn't get me there and back on a single charge. Yesterday the work charger shut off (Green light) at 56.2V - I nearly didn't make it home...
The home charger charged fully to 58.7V - so I think the issue is the charger - the work environment is dusty - grinding and sanding so I'm not surprised it is failing - It shut down completely this morning - wouldn't even power up - I stripped open the case - cleaned with contact cleaner and dried with air - it switched on and charged again to 56.2V before shutting down with a full green indicator. I reckon the dust has damaged something? Anyone with experience in repairing chargers have any pointers or checks I can carry out?


Well-known member
Local time
11:51 PM
Jan 13, 2023
The left coast
Sounds like a charger issue, as you say.

Unfortunately, battery chargers tend to be very cheaply made. Mix them in with a hostile environment and a heavy duty cycle (like charging every day at work) and you see much higher failure rates. At least I sure did for the couple of years I did it before I stepped off the merry go-round... I lost three chargers, all of which were adjustable and rather pricey (although the seller did warranty them).

When I stepped off that merry-go-round, I went this way, and instead of using lowest-bidder kaka equipment I substituted in weatherproof, potted chargers that are meant for use in damp and outside environments on commercial signs and municipal streetlights. The 3a-capable model has a Mean Time Between Failure of...

192,200 hours.

Thats almost 22 years if you leave it plugged in and running continuously. I haven't lost a single charger since I switched to these. On some of my bikes since they are weather proof (IP65) I mount them directly on the bike, so all I have to do is plug into an outlet.