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P1838




P1838 On Switch

Description

The differential lock mode switch sends differential lock ON/OFF request signals to the differential lock control unit.

DTC Logic






Diagnosis Procedure

Regarding Wiring Diagram information, refer to [Differential Lock Control Unit: Wiring Diagram] [1][2]Differential Lock.

1. CHECK DIFFERENTIAL LOCK MODE SWITCH OPERATION

1 Turn ignition switch ON.
2 Using SDT, select "D-LOCK SW SIG" of "Diff Lock" data list items.
3 While operating the differential lock mode switch, check that the display value changes between ON/OFF.






Is the inspection result normal?
YES
Differential lock mode switch is operating properly.
NO
GO TO 2.

2. CHECK DIFFERENTIAL LOCK MODE SWITCH POWER SUPPLY CIRCUIT

1 Disconnect differential lock mode switch harness connector.





2 Turn ignition switch ON.
3 Check voltage between differential lock mode switch harness connector M149 terminal 3 and ground.






Is the inspection result normal?
YES
GO TO 3.
NO
Repair harness or connector.

3. CHECK DIFFERENTIAL LOCK MODE SWITCH SIGNAL

1 Turn ignition switch OFF.





2 Connect differential lock mode switch harness connector.
3 Check voltage between differential lock control unit harness connector M70 terminals 9, 22 and ground.






Is the inspection result normal?
YES
Replace the differential lock control unit. Refer to [Differential Lock Control Unit: Removal and Installation] Service and Repair.
NO
GO TO 4.

4. CHECK DIFFERENTIAL LOCK MODE SWITCH

1 Turn ignition switch OFF.
2 Disconnect differential lock mode switch harness connector.
3 Operate differential lock mode switch and check continuity between differential lock mode switch terminals.











Is the inspection result normal?
YES
GO TO 5.
NO
Replace differential lock mode switch.

5. CHECK HARNESS BETWEEN DIFFERENTIAL LOCK CONTROL UNIT AND DIFFERENTIAL LOCK MODE SWITCH

1 Check continuity between differential lock control unit harness connector M70 (A) terminals 9, 22 and differential lock mode switch harness connector M149 (B) terminals 2, 1.











2 Check continuity between differential lock control unit harness connector M70 (A) terminals 9, 22 and ground.






Is the inspection result normal?
YES
Replace the differential lock control unit. Refer to [Differential Lock Control Unit: Removal and Installation] Service and Repair.
NO
Repair harness or connector.