Dometic Mobicool B40 AC/DC
Official technical documentation and workshop diagnostics for Mobicool B40 AC/DC.
Technical Specifications
Master Troubleshooting & Diagnostics Matrix
| Error Code / Indicator | Symptom / Meaning | Step-by-Step DIY Fix | Suggested Actions |
|---|---|---|---|
N/A | Your device is not working (plug is inserted). No voltage flowing from the DC socket (cigarette lighter) in your vehicle. Possible Cause: The ignition is switched off in most vehicles. | The ignition must be switched on in most vehicles to supply current to the cigarette lighter. | DIY Safe |
N/A | Your device is not working (plug is inserted). No voltage present in the AC voltage socket. Possible Cause: Socket is unpowered. | Try using another plug socket. | DIY Safe |
N/A | The inner fan, cooling element, or compressor is not working. Possible Cause: Component is defective. | This can only be repaired by an authorised repair centre. | Professional Intervention Required |
N/A | When operating from the DC socket (cigarette lighter): The ignition is on and the cooler is not working, and the DC plug becomes very warm. Possible Cause: The fuse of the DC plug is dirty, resulting in poor electrical contact, or the plug has not been assembled correctly. | Clean the DC socket fitting or ensure the plug is correctly assembled. | DIY Safe |
N/A | When operating from the DC socket: The ignition is on and the cooler is not working, DC plug fuse blown. Possible Cause: Blown fuse inside the DC plug. | Replace the fuse of the DC plug with one of the same rating. | DIY Safe |
N/A | When operating from the DC socket: The ignition is on and the cooler is not working, vehicle fuse blown. Possible Cause: Blown vehicle DC socket fuse. | Replace the vehicle's DC socket fuse (usually 15 A) according to your vehicle's operating manual. | DIY Safe |
Frequently Asked Questions
Q: What does climate class of SN (Sub Normal) mean?
The climate class SN (Sub Normal) defines the intended ambient temperature range for the absorption fridge's optimal operation.
Q: What’s the cooling performance in warmer ambient temperatures?
Cooling performance for absorption fridges is affected by warmer ambient temperatures. Ensure proper ventilation around the unit as detailed in the manual to maintain performance.
Q: How to operate an RMxxxx with a solar panel?
To operate an RMxxxx series absorption fridge with a solar panel, ensure the solar system provides adequate 12V DC power or sufficient battery storage to handle the power requirements, particularly when running on DC mode.
Q: My RMxxxx needs to be replaced. What would be an alternative?
When replacing an RMxxxx series refrigerator, look for current Dometic absorption or compressor models matching the physical dimensions and energy source requirements of your motorhome cutout.
Q: The refrigerator does not work In AC power mode?
Check if the vehicle is properly connected to the AC mains supply, verify that the AC fuse in the motorhome is intact, and ensure the refrigerator is switched on to AC mode on the control panel.
Q: The refrigerator does not work In DC power mode?
DC mode (12V) typically only works while the vehicle engine is running and the alternator is supplying power, preventing the vehicle starter battery from draining. Check the 12V DC fuses, vehicle ignition connection, and input voltage at the refrigerator terminals.
Q: The refrigerator does not work In GAS mode?
Ensure the gas cylinder valve is open, the main gas shut-off valves in the motorhome are open, and there is no air trapped in the gas line (try igniting another gas appliance first). Check if the igniter is sparking and that the burner is clean.
Q: In automatic mode: The refrigerator is being operated with gas although it is connected to The AC power supply?
In automatic energy selection mode, if the AC voltage is outside the acceptable tolerance range or unstable, the control system automatically switches to gas mode as a safety fallback. Check the AC supply voltage and connections.
Q: The refrigerator is not cooling adequately?
Verify that ventilation grilles are not blocked, check that the thermostat is set correctly, ensure the door seals tightly, do not overpack the interior restricting airflow, and verify that the selected energy source (AC, DC, or Gas) is actively functioning.
Q: WARNING type fault messages
WARNING type fault messages indicate a non-critical operational issue or prompt. Consult the user manual for the specific warning code displayed on the 10-series control panel to take corrective action.
Q: ERROR type fault messages
ERROR type fault messages indicate a critical system failure that stops the refrigerator from functioning safely on the current energy source. Check the specific error code on the display, troubleshoot the underlying power, gas, or ventilation issue, or contact customer service.