Charger completely dead: no LEDs, no display, and no relay click when power is applied.

Safety: Work on mains circuits must be done by qualified persons.

• Check breaker: Verify that the dedicated breaker feeding the ABB charger is in the ON position and has not tripped. Reset if necessary.
• Test outlet/circuit: If the charger is plug-in type, test the receptacle with another high-load device. For hardwired units, an electrician should measure voltage at the input terminals.
• Inspect internal fuse (technician): With power off, open the charger and locate any internal fuses on the input or control board. Test and replace with identical ABB-specified fuses if blown.
• Check for visible damage: Look for burn marks or damaged components on the power and control boards. If found, disconnect power and arrange for professional repair.
• Board replacement: If supply and fuses are good but the unit remains dead, the auxiliary power supply on the control board is likely failed and the board should be replaced.