Diagnosis Procedure
REAR WINDOW DEFOGGER SWITCH
Description
- The rear window defogger is operated by pressing the rear window defogger switch ON.
- The indicator lamp in the rear window defogger switch illuminates while the rear window defogger is ON.
REAR WINDOW DEFOGGER SWITCH
Diagnosis Procedure
Regarding Wiring Diagram information, refer to Coupe (Coupe) or Sedan (Sedan).
1.CHECK REAR WINDOW DEFOGGER RELAY OPERATION
Check that an operation noise of rear window defogger relay [located in fuse block (J/B)] can be heard when pressing the rear window defogger switch ON and OFF.
Is the inspection result normal?
YES - GO TO 2
NO - GO TO 5
2.CHECK FUSE
Check if Fuse 13 from the rear window defogger relay output is blown.
Is the fuse blown?
YES - Replace the blown fuse after repairing the affected circuit.
NO - GO TO 3
3. CHECK FOR VOLTAGE FROM THE REAR WINDOW DEFOGGER RELAY
1. Connect a voltmeter between Fuse 13 and ground.
2. While pressing the rear window defogger switch ON and OFF, check for voltage between Fuse 13 and ground.
Is the inspection result normal?
YES - GO TO 4
NO - GO TO 11
4.CHECK REAR WINDOW DEFOGGER SWITCH INDICATOR CIRCUIT
1. Press rear window defogger switch
2. Check for voltage between front air control connector and ground.
Is the inspection result normal?
YES - Replace front air control. Refer to Service and Repair.
NO - Repair or replace harness.
5.CHECK FRONT AIR CONTROL FUNCTION
CONSULT-III
1. Select BCM (REAR DEFOGGER) DATA MONITOR.
2. While pressing and releasing the rear window defogger switch, check that the switch state changes between ON/OFF.
Is the inspection result normal?
YES - GO TO 8
NO - GO TO 6
6. CHECK REAR WINDOW DEFOGGER ON SIGNAL CIRCUIT
1. Push ignition switch to ON.
2. Check voltage between BCM connector M18 terminal 38 and ground.
Is the inspection result normal?
YES - Replace BCM. Refer to BCM.
NO - GO TO 7
7. CHECK HARNESS CONTINUITY
1. Push ignition switch to OFF.
2. Disconnect BCM and Front Air Control.
3. Check continuity between BCM connector and front air control connector.
4. Check continuity between BCM harness connector M18 terminal 38 and ground.
Is the inspection result normal?
YES - Replace front air control. Refer to Service and Repair.
NO - Repair or replace harness.
8.CHECK BCM REAR WINDOW DEFOGGER RELAY CONTROL FUNCTION
CONSULT-III
1. Select BCM (REAR DEFOGGER) ACTIVE TEST.
2. Turn REAR DEFOGGER active test ON.
3. Check that an operation noise of rear window defogger relay [located in fuse block (J/B)] can be heard when REAR DEFOGGER active test is turned ON.
Is the inspection result normal?
YES - Replace BCM. Refer to BCM.
NO - GO TO 9
9. CHECK REAR WINDOW DEFOGGER RELAY GROUND CIRCUIT
CONSULT-III
1. Push the ignition switch to ON.
2. Select BCM (REAR DEFOGGER) ACTIVE TEST.
3. Turn REAR DEFOGGER active test ON.
4. Check voltage between fuse block (J/B) connector M4 terminal 4Q and ground.
Is the inspection result normal?
YES - GO TO 12
NO - GO TO 10
10. CHECK REAR WINDOW DEFOGGER RELAY CIRCUIT
1. Push ignition switch to ON.
2. Check voltage between fuse block (J/B) connector M4 terminal 4Q and ground.
Is the inspection result normal?
YES - GO TO 11
NO - Replace rear window defogger relay.
11. CHECK HARNESS CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect BCM and fuse block (J/B).
3. Check continuity between BCM connector M18 terminal 59 and fuse block (J/B) connector M4 terminal 4Q.
4. Check continuity between fuse block (J/B) connector M4 terminal 4Q and ground.
Is the inspection result normal?
YES - Replace BCM. Refer to BCM.
NO - Repair or replace harness.
12. CHECK REAR WINDOW DEFOGGER RELAY
Check rear window defogger relay. Refer to Component Inspection.
Is the inspection result normal?
YES - GO TO 12
NO - Replace rear window defogger relay.
13. CHECK INTERMITTENT INCIDENT
Check intermittent incident. Refer to Intermittent Incident.
Is the inspection result normal?
YES - Check the following.
- Battery power supply circuit.
- Fuse block (J/B).
NO - Repair or replace the malfunctioning parts.