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Webasto diesel heater isn't working - TrailLite models

This article includes the possible fault codes on a Webasto diesel space heater and how to clear or fix it based on the codes

Error Detail  Fix
H02 Flame failure

The heater failed to ignite:

  • Pull the 20amp heater fuse and wait 30 seconds before re-fitting it.
  • Clear the faults on the gauge by resetting it and try the heater again.
  • Repeat this fix a handful of times if the fault reoccurs.
  • If still not working after many attempts then check the fuel pump and fuel source.
T12 Electrical fault

Electrical fault at heater:

  • Check if fuses are blown first - replace if necessary and determine what has blown the fuses.
  • If fuses aren't blown then check main harness is fully plugged into the heater.
H94 Temperature sensor failure

Temperature sensor failure detected:

  • Ensure the supplied resistor has been fitted to the wires on the heater labelled "temperature sensor" on the heater loom. (2KW Heater only)
H07
 
Lock out mode

The heater has faulted too many times and gone into lock mode.

  • Perform a full heater reset by removing all fuses for 30 seconds then re-fitting them.
  • Clear all the faults on the controller by resetting it.
  • Then try running the heater again.