Safety first: Overheating can damage components. Allow the charger to cool before opening the housing. Isolate power at the breaker.

1. Check installation environment:
- Ensure the charger is not exposed to direct midday sun without shading.
- Verify there is adequate clearance around the unit for airflow as per Heidelberg manual.
2. Inspect ventilation and fan:
- Check that all ventilation grilles are free from dust, cobwebs, or debris.
- Open the housing and visually inspect the cooling fan (if fitted).
- Spin the fan gently by hand (with power off) to ensure it is not seized.
3. Power up and observe fan operation:
- Re‑energize the charger with the cover temporarily in place (or as allowed by service procedure).
- Start a charging session and confirm the fan starts when load is applied.
4. Check temperature sensor connections:
- Locate the NTC temperature sensor on the power module or heatsink.
- Ensure its connector is firmly seated on the main control board.
5. If E05 recurs quickly:
- The fan or temperature sensor may be defective and should be replaced with Heidelberg‑approved parts.
- Persistent overtemperature may indicate a failing power module; contact a service technician.

Charger displays E05, fan may run briefly, then unit shuts down and will not start charging.

Possible Causes