C1248

BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM: C1248/48: Open Circuit in Rear Differential Lock
C1248/48 - Open Circuit in Rear Differential Lock

DESCRIPTION

The 4WD control ECU stimulates the actuator to lock the rear differential in accordance with the rear diff. lock switch. The skid control ECU monitors the transfer indicator switch (rear diff. lock ) and if the rear differential is locked, at which time the rear diff. lock indicator light is illuminated, prohibits ABS control. At the same time, the skid control ECU illuminates the ABS warning light.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. INSPECT SKID CONTROL ECU (EXI2 TERMINAL VOLTAGE)

(a) Disconnect the skid control ECU connector.





(b) Turn the ignition switch to ON.

(c) Measure the voltage according to the value(s) in the table below.

(d) Check the rear diff. lock indicator light.

Standard:





Text in Illustration





NG -- INSPECT TRANSFER INDICATOR SWITCH (REAR DIFF. LOCK)
OK -- Continue to next step.

2. RECONFIRM DTC

(a) Clear the DTCs ABS (Antilock Brake System).

(b) Drive the vehicle at a speed of 50 km/h (31 mph) or more for 3 seconds or more with the rear differential free.

(c) Check if the same DTCs are recorded.

Result





B -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOMS SIMULATION)

A -- REPLACE BRAKE ACTUATOR ASSEMBLY

3. INSPECT TRANSFER INDICATOR SWITCH (REAR DIFF. LOCK)

(a) Disconnect the transfer indicator switch connector.





(b) Remove the transfer indicator switch.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE TRANSFER INDICATOR SWITCH
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Disconnect the skid control ECU connector.

(b) Disconnect the 4WD control ECU connector.

(c) Disconnect the transfer indicator switch connector.

(d) Turn the ignition switch to ON.

(e) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





NG -- CHECK HARNESS AND CONNECTOR

OK -- REPLACE 4WD CONTROL ECU

5. CHECK HARNESS AND CONNECTOR

(a) Disconnect the skid control ECU connector.

(b) Disconnect the 4WD control ECU connector.

(c) Disconnect the transfer indicator switch connector.

(d) Disconnect the combination meter connector.

(e) Measure the resistance according to the value(s) in the table below.





Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE COMBINATION METER Removal