Rear Window Defogger Switch Circuit Check

With CONSULT-II 

Check ("REAR DEF SW", "IGN ON SW") in DATA MONITOR mode with CONSULT-II. Refer to "DATA MONITOR ".

When rear window defogger switch is turned to ON 

REAR DEF SW : ON 

When ignition switch is turned to ON 

IGN ON SW : ON 

Fig 1: CONSULT-II Function Screen Display - DATA MONITOR

Without CONSULT-II 

1. Turn ignition switch ON.
2. Check voltage between BCM connector and ground.
   CONNECTOR TERMINALS REFERENCE CHART
   
   

   Connector	Terminals		Condition	Voltage (V) (Approx.)
   	(+)	(-)
   M18	9	Ground	Rear window defogger switch is pressed.	0
   			Rear window defogger switch is OFF.	5

   Fig 2: Checking Voltage Between BCM Connector And Ground

   

OK or NG 

OK: Rear window defogger switch check is OK.

NG: GO TO 2.

1. Turn ignition switch OFF.
2. Disconnect BCM and front air control.
3. Check continuity between BCM connector M18 terminal 9 and front air control connector M49 terminal 11.

   9 - 11 : Continuity should exist. 

4. Check continuity between BCM connector M18 terminal 9 and ground

   9 - Ground : Continuity should not exist. 

   Fig 3: Checking Continuity Between BCM Terminal M18 Front Air Control Connector Terminal And Ground

   

OK or NG 

OK: GO TO 3.

NG: Repair or replace harness.

1. Connect BCM.
2. Turn ignition switch ON.
3. Check voltage between BCM connector M18 terminal 9 and ground.

   9 - Ground : Approx. 5 

OK or NG 

OK: Replace front air control. Refer to "FRONT AIR CONTROL ".

NG: Replace BCM. Refer to "REMOVAL AND INSTALLATION ".

Fig 4: Checking Voltage Between BCM Connector And Ground