BMW EV charger shows E03 and will not energize; LED ring red or flashing red/white

Safety first: Do not attempt to bypass any RCD or ground-fault protection. Turn off the breaker before inspection.

• Check for moisture: Inspect the Type 2 plug and cable for signs of water, condensation, or corrosion. If the plug has been lying on the ground outdoors, dry it thoroughly with a clean cloth and allow several hours in a dry environment.
• Inspect cable jacket: Look for cuts, abrasions, or crushed sections along the BMW Wallbox cable. Any exposed conductor requires immediate replacement of the cable assembly.
• Test with another vehicle: If possible, connect a different EV. If E03 only appears with one vehicle, the fault may be in that vehicle's onboard charger or inlet.
• Reset RCD: If your BMW Wallbox has an external RCD/RCBO in the distribution panel, reset it after verifying there is no visible damage. Then power up the Wallbox and check if E03 clears.

Persistent E03 with multiple vehicles and a dry, undamaged cable indicates a defective internal RCD or sensing circuit. This is a safety-critical component; contact a BMW-certified electrician to replace the internal RCD module or the entire Wallbox, as specified by BMW service documentation.