Bosch Short Circuit or Ground Fault on Output

Bosch EV charger trips the upstream breaker or GFCI immediately when a vehicle is plugged in.

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Shorted conductors in output cable, Water inside J1772 handle, Internal short on main PCB, Incorrect wiring polarity at input terminals

How to Fix / Troubleshooting

Safety first: Do not repeatedly reset a tripping breaker. This indicates a potentially dangerous fault.

  • Visual cable check: Inspect the entire length of the Bosch cable for cuts, crushed sections, or melted insulation. Do not use the charger if any damage is found.
  • Check handle for moisture: Look for water droplets or condensation inside the J1772 handle. If present, leave the breaker OFF and allow the handle to dry thoroughly.
  • Test without vehicle: Turn ON the breaker with no vehicle connected. If the breaker holds, but trips only when plugging in, the fault is likely in the cable/handle or vehicle.
  • Professional diagnosis: An electrician or technician should perform insulation resistance tests on the cable and inspect the main PCB for shorts. Replace the damaged cable assembly or board as needed.
Advertisements

Repair Difficulty

Professional Required 5/5

Required Part

Bosch J1772 Charge Cable and Handle Assembly
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements