C1909

C1909 4WAS MAIN CONTROL UNIT





DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE
1.RECHECK DTC
With CONSULT-III
1. Turn the ignition switch from OFF to ON.
2. Perform self-diagnosis for "4WAS(MAIN)/RAS/HICAS".
Is DTC "C1909" detected?
YES - Proceed to diagnosis procedure. SEE Diagnosis Procedure.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK 4WAS MAIN CONTROL UNIT GROUND
1. Turn the ignition switch OFF.
2. Disconnect 4WAS main control unit harness connector.
3. Check the continuity between 4WAS main control unit harness connector terminal and the ground.





Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace the harnesses and connectors.
2.CHECK 4WAS MAIN CONTROL UNIT POWER SUPPLY (1)
1. Check the voltage between 4WAS main control unit harness connector terminal and ground.





2. Turn the ignition switch ON.

CAUTION:
Never start the engine.
3. Check the voltage between 4WAS main control unit harness connector terminal and ground.





Is the inspection result normal?
YES - GO TO 4.
NO - GO TO 3.
3.CHECK 4WAS MAIN CONTROL UNIT POWER SUPPLY (2)
1. Turn the ignition switch OFF.
2. Check the 10A fuse (#46).
3. Disconnect IPDM E/R harness connector.
4. Check the continuity between 4WAS main control unit harness connector and IPDM E/R harness connector.





5. Check the continuity between 4WAS main control unit harness connector and ground.





Is the inspection result normal?
YES - Perform the trouble diagnosis for ignition power supply circuit. Ignition Power Supply, "Wiring Diagram -
IGNITION POWER SUPPLY -".
NO - Repair or replace error-detected parts.
4.PERFORM SELF-DIAGNOSIS (4WAS MAIN CONTROL UNIT)
With CONSULT-III
1. Connect 4WAS main control unit harness connector.
2. Connect IPDM E/R harness connector.
3. Perform self-diagnosis for "4WAS(MAIN)/RAS/HICAS".
Is DTC "C1909" detected?
YES - Replace 4WAS main control unit. 4WAS Main Control Unit.
- Before replacing 4WAS main control unit, record the self-diagnosis results(history). STC-
137, "Special Repair Requirement".
NO - GO TO 5.
5.CHECK INFORMATION
With CONSULT-III
Check the "DATA MONITOR" value of each DTC detected with the self-diagnosis function. 4WAS Main Control Unit, "Reference Value".
Is each data the standard value?
YES - Check each harness connector pin terminal for disconnection.
NO - Replace 4WAS main control unit. 4WAS Main Control Unit.
- Before replacing 4WAS main control unit, record the self-diagnosis results(history). SEE Special Repair Requirement.




Special Repair Requirement
Before replacing 4WAS main control unit, record the self-diagnosis results (history).

CAUTION:
- Never erase the memory (history) of self-diagnosis results when replacing 4WAS main control unit after diagnosis.
- Erase the memory of the self-diagnosis results (record) after printing out or recording all the values of "DATA MONITOR".