Uppsala Support: Auxiliary Heating

Modified on Mon, 4 Mar at 1:04 PM

If the diesel auxiliary heating in your camper isn't working, please follow these steps: First, ensure that the diesel tank is at least a quarter full and that the heater is set to diesel mode. Also, check the Truma display above the driver's door for any error codes. Simply activate the display, and it will immediately show any messages.


A common error code is W412H, which indicates that the window directly above the heating outlet is open. In this case, closing the window should resolve the issue.


If a different error code appears, please get in touch with us.


Additionally, you can reset the heating system itself. To do this, activate the display and then turn the black button until a wrench symbol flashes. Confirm by pressing the button, turn to Reset, and confirm again. It may take a few minutes for the system to reset.

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