A power cut in your motorhome, van, Urban Camper or caravan can be unsettling - especially when travelling. But not every darkness means a defect. This article helps you to understand the actual sources of supply and to check them specifically.
Possible causes at a glance
- Bodywork battery: Deep discharge or defect, disconnection by battery main switch or BMS, interrupted cable connection - without a functioning battery there is no on-board power.
Alternator & charging booster: Defective alternator or charge controller, charging booster does not switch through, battery disconnected or defective - alternator and charging booster are technically linked; if one fails, the battery is not charged.
What is a charging booster? A charging booster is a device that optimises the voltage of the alternator in order to charge the batteries more efficiently, especially in vehicles with modern motors that do not deliver consistently high voltages due to regulations. It ensures that a stable charging voltage is maintained even with fluctuating alternator output.
- 230 V shore power: No connection or defective power outlets, RCD tripped, cable break or incorrect connection. Problems with a built-in inverter can also affect the power supply in the 230 V circuit, as this interferes with the conversion of DC to AC current.
Solution approaches
These steps refer to the 12 V circuit:
- Check the main fuses next to the battery: Check the main fuses right next to the battery, which are often located in a box or plug-like holder. Watch out for blown fuses or loose contacts, as these are critical for the flow of current in the 12 V circuit and must be firmly plugged in.
- Check the EBL switch and fuses: Check all switches on the EBL. Ensure that fuses and switches are inserted correctly, as a misalignment or blown fuses can block the flow of current in the 12 V circuit.
- Enable control panel: Models such as the Schaudt LT631, LT632 or LT633 have a deep sleep mode and communicate with the EBL via LIN bus. If the vehicle is not used for a longer period of time or the battery is low, the system can switch to this mode and the display remains dark as the EBL actively switches off the power circuits. This means that all loads are de-energised, even if the battery still has voltage. Reactivation is only possible by pressing the rotary/push button on the panel for several seconds, provided that the battery is sufficient and the bus communication is intact.
- Connect 230 V shore power and test: Connect your vehicle to a stable external power source. Look for the fuses, which are often located in the cupboards, and check whether the RCDs have tripped. If the loads in the 230 V circuit are working, this indicates that the external power source is working and the battery is being charged.
- Start motor: Use the motor to check that you can generate power and that your 12 V supply is restored. Observe whether electrical loads in the vehicle are reactivated, which is a sign that the alternator is working properly and supplying power.
These steps refer to the 230 V circuit:
- Check the fuse in the cupboard: Check the fuses in the cupboard and see if the RCDs have tripped. No more shore power may indicate a tripped RCD or an external connection fault.
- Check the inverter: If an inverter is installed, check it for proper fuses and 12 V supply circuit. Problems with the inverter can affect the conversion and availability of electricity in the 230 V circuit.
When is professional help necessary?
If one of the test options does not produce the desired result or if there is still no full power supply, it is advisable to contact a Bürstner service partner for a detailed check.
⚠️ Safety note
Start troubleshooting in your vehicle without touching the electrical components directly. Take care to identify visible signs of problems, such as loose cables or blown fuses. If you are unsure or do not understand the system, call a specialist to help you resolve the problem safely.
💡 Our tip
Regular checks of the main fuses and a clean battery installation contribute significantly to the reliable functioning of the electrical system and help you to recognise signs of problems at an early stage.
This website uses automatic translations. Please excuse any errors. In case of doubt, the original German version applies.