Charger shows E19; vehicle may not recognize the charger or shows communication error.

Safety: Handshake issues are low-voltage but always disconnect from mains before physical inspection.

• Reconnect both ends: Unplug from vehicle and mains, then reconnect mains first, then vehicle.
• Wait before retrying: Allow 1–2 minutes between attempts so the vehicle can reset its charging controller.
• Try another vehicle: If E19 only occurs with one car, the issue is likely in that vehicle.
• Check cable and connector: Inspect for damage or contamination that could affect pilot or proximity lines.
• Persistent E19 on multiple vehicles: Indicates a likely timing or communication fault on the J+ Booster main control board; professional diagnosis is required.