BMS (Battery Management System)

The BMS protects your battery by balancing cells and cutting power on faults. When it fails, the pack may not charge, shut off randomly, or show wrong charge levels even with good cells.

Find a Technician

Common causes

BMS tripping and cutting output under load
Cell balancing failure inside the pack
Overcurrent or short-circuit damage
Water or corrosion on the BMS board
Wrong charge reading from a faulty BMS
Firmware or sensor fault on the board

Frequently asked questions

How do I know if it's the BMS and not the cells?

If the cells test healthy but the pack won't charge or cuts out, the BMS is usually the culprit. A diagnostic confirms it.

Can a BMS be replaced on its own?

Yes - in many packs the BMS is a separate board that can be swapped without replacing the cells, saving money.

How it works

Describe the issue

Tell us what's going on with your car. Our platform matches you with verified providers who handle this exact problem.

Connect with a provider

Browse verified mobile mechanics and auto service pros near you. Read real reviews and pick the best fit.

Get it fixed

Your provider comes to your location, diagnoses the issue on the spot, and gets you back on the road.