3360261 - J21 HEATED REAR WINDSCREEN NOT WORKING

When the key on the control panel is pressed, the heated rear window demister does not work.

The rear wiper motor power supply is protected by a specific fuse and controlled by a relay, both housed in the underfacia junction unit. When the command is received, the body computer node excites the relay coil via an earth signal. The coil closes the switch and activates the heated rear window.

		Results of the tests
0	PRELIMINARY CHECK	All OK	Problems met	Operation
	Check that the heated rear window fuse is not blown See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING	Continue to Step 1	Fuse blown	Change fuse See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
1	CHECK USING TESTER	All OK	Problems met	Operation
	Connect an Examiner and check operation of the heated rear window supply control relay. See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING	Continue to Step 2	Relay not working.	Replace relay See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
2	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Keep the Examiner connected and check heated rear window demister switch status has been properly downloaded while in parameter mode.	Continue to Step 3	Malfunction in download of heated rear window demister control switch status.	Continue to Step 6
3	CHECKING ELECTRICAL CIRCUIT	All OK	Problems met	Operation
	Check continuity/insulation of electrical connection between body computer node and heated rear window See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING	Continue to Step 4	Electrical connection interrupted or not insulated.	Restore electrical connection continuity/insulation See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
4	CHECKING ELECTRICAL CIRCUIT	All OK	Problems met	Operation
	Check heated rear window earth electrical connection continuity/insulation: See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING	Continue to Step 5	Electrical connection interrupted or not insulated.	Restore electrical connection continuity/insulation See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
5	CHECKING ELECTRICAL CIRCUIT	All OK	Problems met	Operation
	Check heated rear window power supply	Continue to Step 9	No supply	Change body computer node Op. 5505A32
6	CHECKING ELECTRICAL CIRCUIT	All OK	Problems met	Operation
	Check continuity/insulation of the electrical connection between body computer node and heated rear window demister control switch. See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING	Continue to Step 7	Electrical connection interrupted or not insulated.	Restore electrical connection continuity/insulation See   E3030  HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
7	CHECK SWITCH	All OK	Problems met	Operation
	Check the heated rear window demister control switch is working properly	Continue to Step 8	Switch malfunction	Change the heated rear window demister control switch. Op. 5040D18
8	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	The fault persists	Change body computer node Op. 5505A32
9	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	The fault persists	Replace heated rear window Op. 7035B14Search for the fault starting from another symptom'