FIAT / DUCATO 244eLearn workshop manual · English · Offline edition
Fault diagnosis

J20 REARSCREEN AND DOOR MIRROR DEFROSTING NOT WORKING

Engines: 2.0 16V, 2.0 JTD 8V, 2.3 JTD 16V, 2.8 JTD 8V
Engines: 2.0 16V
Equipment / version codes: Minibus [B33], Van [B34], Panorama [B36], Combi [B37]
The demisting function does not work when the button is pressed with the ignition on.
Engines: 2.0 16V
Equipment / version codes: Minibus [B33], Van [B34], Panorama [B36], Combi [B37]
STEPOPERATIONS TO BE CARRIED OUTTEST RESULTS
0PRELIMINARY CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check fuse condition See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTINGMove on to StepFuse blown1. Replace the fuse and find out what could have caused it to blow
1RESISTANCE CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Using a multimeter, check that the heated rear windscreen/mirror's resistance is not broken See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTINGMove on to Step1. Resistances broken at the heated rear windscreen(s)1. Renew the resistance or replace the heated rear windscreen(s)
2. Resistance at mirror broken2. Replace the mirror
2HEATED REAR WINDSCREEN/REAR VIEW MIRROR HEATING RESISTANCES POWER SUPPLY CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check that when the appropriate button in the switch panel is operated there is a corresponding operating voltage for the resistances at the heated rear windscreen and the rear view mirrors See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTINGMove on to StepNo supply for resistancesMove on to Step
3HEATED REAR WINDSCREEN RELAY CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the heated rear windscreen relay is working properly See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTINGMove on to StepHeated rear windscreen relay defectiveReplace the heated rear windscreen relay See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
4HEATED REAR WINDSCREEN/REAR VIEW MIRRORS DEMISTING ELECTRIC CIRCUIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the following, in order:
  • Connections between switch control panel and underfacia junction unit
  • Connections between underfacia junction unit and rear view mirrors
  • Connections between underfacia junction unit and heated rear windscreen(s)
  • Rear view mirror earths
  • Heated rear windscreen earths
Move on to Step1. Component defective1. Replace the component
2. Connections interrupted2. Repair the connections See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
5IGNITION SWITCH CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the ignition switch is operating correctly: particularly the heated rear windscreen relay feed See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTINGMove on to StepIgnition switch faultRepair or replace the ignition switch Op. 5520A12 IGNITION SWITCH ASSEMBLY - R R FOR VERSIONS WITH AIR BAG
6SWITCH CONTROL UNIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the following, in order:
  • Correct power supplies/earths to switch control unit
  • Check that an earth signal is generated to operate the heated rear windscreen relay when the rearscreen demisting button is activated
Move on to Step1. Power supplies/earths incorrect1. Restore correct power supplies/earths See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
2. Switch control panel defective2. Replace switch control unit Op. 5505A24 W/L AND SERVICE SWITCH MOUNT - R+R
7UNDERFACIA JUNCTION UNIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the following, in order:
  • Correct underfacia junction unit power supply/earths
  • Check that when an earth signal is produced by the switch control panel for the underfacia junction unit there is an operating voltage for the heated rear windscreen(s) and the rear view mirrors
Move on to Step1. Power supplies/earths incorrect1. Restore correct power supplies/earths See E3030 HEATED REAR WINDSCREEN AND DOOR MIRROR DEFROSTING
2. Underfacia junction unit defective2. Replace the underfacia junction unit
8CHECK ON CORRECT OPERATIONALL OKPROBLEMS ENCOUNTEREDACTION
Check that the fault is no longer present