I’m having trouble with my 48v ebike battery charger. It takes much longer than usual to charge the battery, and sometimes the charger light doesn’t change from red to green even after hours of charging. I’ve checked the battery, and it seems fine, so I’m wondering if the charger itself is the issue. What should I check to fix this 48v ebike battery charger problem 
The first thing to check is the charger’s power supply. Make sure the outlet is working properly. Sometimes, a faulty power outlet can cause the charger to not function correctly. Try plugging it into a different outlet to see if that resolves the issue.
Charger cables can wear out over time. Check the charger’s cable for any visible damage, fraying, or bends. A damaged cable can prevent proper charging and may even cause overheating or electrical shorts.
If the charger light stays red and doesn’t turn green, it could indicate that the battery isn’t accepting charge properly. This could be caused by a problem with the battery’s BMS (battery management system) that’s preventing charging.
I didn’t realize the BMS could cause this
Check the charger’s voltage output. Use a multimeter to ensure that the charger is providing the correct voltage (48V) as specified. If the charger’s voltage is too low or too high, it could be damaged or faulty.
Sometimes, a dirty or corroded charging port on the battery can cause poor charging connection. Check the charging port on the battery and the charger plug for dust, dirt, or corrosion. Cleaning them gently can improve the connection.
I’ve experienced similar problems with a charger that overheated due to poor ventilation. If the charger is overheating, it may shut off as a safety feature. Make sure the charger is in a well-ventilated area while charging.
If the charger is several years old, it could be worn out and need replacing. Even high-quality chargers can degrade over time. Testing with a different charger (if you have one) can help confirm if the charger is the problem.
In some cases, the battery itself might have an issue that prevents it from charging correctly. If the battery is old or has been through many charge cycles, it could have developed a fault that’s preventing it from accepting a full charge.
Before replacing the charger, try resetting the battery. Disconnect the battery and charger for a few minutes, then reconnect and try charging again. This can sometimes reset the system and fix charging issues.
I’ll try resetting the battery
If the charger is still under warranty, it’s worth contacting the manufacturer to see if they’ll replace it. Some warranties cover defects or issues like this.
A faulty charger can be a simple fix if it’s a connector issue, but if the charger itself is broken, you may need to replace it with a new one that matches the specifications of your 48v battery.
I will look into getting a replacement charger if needed