J+ Booster Relay Chatter / Unstable Control

Charger makes a rapid clicking sound and repeatedly starts and stops charging within seconds.

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.

Possible Causes

Unstable mains voltage causing repeated undervoltage detection, Faulty control logic on main control board, Loose low-voltage harness to relay driver, Overly sensitive current or ground fault sensor oscillating

How to Fix / Troubleshooting

Safety: Rapid switching can stress relays and connectors. Avoid repeated attempts.

Disconnect and wait: Unplug the charger and let it sit for 10 minutes.
Test on another circuit: Use a different, stable outlet to rule out supply fluctuations.
Reduce current setting: If possible, lower the current and test again.
If clicking persists on a stable supply: The main control board or relay driver circuitry is likely faulty and requires professional repair.

Repair Difficulty

Hard 4/5

Required Part

J+ Booster Main Control Board

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