3233070 - J20 REARSCREEN AND DOOR MIRROR DEFROSTING NOT WORKING

With the ignition on, when the appropriate button on the climate control panel is pressed, the heated rear window and the door mirrors do not warm up properly.
If the battery voltage is below 11.6 V, the heated rear window and door mirrors are not supplied by the control unit.
Results of the tests
0PRELIMINARY CHECKSAll OKProblems metOperation
Check that neither the rear window nor door mirror demisters work Continue to Step 1 Only the rear window does not work See table   J21 
Only the door mirrors do not work See table   J22 
1CHECKING DEMISTER ACTIVATION LEDAll OKProblems metOperation
When the button on the climate control panel is pressed, check that the led on the button comes on to indicate that the function is activated. Continue to Step 2 Demister led does not come onRestore the connection between climate control unit and service control unit ( See   E3020  WINDSCREEN WASH/WIPE ). Continue to Step 3
2DEMISTING ELECTRICAL CIRCUIT CHECKAll OKProblems metOperation

Check, in order:

  • heated rear windscreen fuse
  • heated rear windscreen relay
  • connection between heated rear window relay and service control unit
  • services control unit supply
( See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING ). 		Continue to Step 3 Connections not correctRestore the connections
Component defectiveReplace the component involved (if a fuse is involved, search for the cause of the problem)
3SERVICES CONTROL UNIT CHECKAll OKProblems metOperation
Check that the services control unit is working properly, in particular the rear window and door mirror demister function; see DESCRIPTION AND OPERATION: 5505 ELECTRICAL CIRCUIT FOR INSTRUMENTS/INDICATORS Continue to Step 4 Control unit not working Replace the services control unit Op.   5505A18 
4CHECK CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom'