Inspection Procedure 3
INSPECTION PROCEDURE 3: Shifting the S-AWC control mode selector does not change the mode
CAUTION:
- If there is any problem in the CAN bus lines, an incorrect trouble symptom may occur. Prior to this diagnosis, always diagnose the CAN bus lines.
- Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
SYMPTOMS
S-AWC control mode selector or AWC-ECU may have a problem.
PROBABLE CAUSES
- S-AWC control mode selector malfunction
- Malfunction of the combination meter
- Damaged harness wires and connectors
- Malfunction of AWC-ECU
DIAGNOSTIC PROCEDURE
STEP 1. M.U.T.-III CAN bus diagnostics.
Use scan tool to perform the CAN bus diagnosis.
Q. Is the check result normal?
YES Go to Step 3.
NO Repair the CAN bus lines. CAN Bus Diagnostics Chart). After repairing the CAN bus line, go to Step 2.
STEP 2. Retest the system.
Q. Is the check result normal?
YES Intermittent malfunction. How to Cope With Intermittent Malfunctions).
NO Go to Step 3.
STEP 3. M.U.T.-III actuator test.
Combination meter item No.2: LCD(AUTO) Actuator Test Reference Table).
Q. Is the check result normal?
YES Go to Step 4.
NO Replace the combination meter. Removal and Replacement). Then go to Step 13.
STEP 4. S-AWC control mode selector inspection
Refer to S-AWC Control Mode Selector Inspection.
Q. Is the check result normal?
YES Go to Step 5.
NO Replace the S-AWC control mode selector (Refer to Service and Repair). Then go to Step 13.
STEP 5. Measure the voltage at C-41 S-AWC control mode selector connector.
(1)Disconnect the connector, and measure the voltage between terminal No.1, No.3 and ground at the harness side.
(2)Turn the ignition switch to the "ON" position.
OK: Battery positive voltage
Q. Is the check result normal?
YES Go to Step 8.
NO Go to Step 6.
STEP 6. S-AWC control mode selector connector, intermediate connector, AWC-ECU connector check: C-41, C-32, C-138, C-139
Q. Is the check result normal?
YES Go to Step 7.
NO Repair the defective connector. Then go to Step 13.
STEP 7. Check the wiring harness between C-41 S-AWC control mode selector connector terminal No.1 and C-139 AWC-ECU connector terminal No.6, and between C-41 S-AWC control mode selector connector terminal No.3 and C-139 AWC-ECU connector terminal No.7.
Check the output line for short or open circuit.
Q. Is the check result normal?
YES Go to Step 11.
NO Repair the wiring harness. Then go to Step 13.
STEP 8. Measure the resistance at C-41 S-AWC control mode selector connector.
Disconnect the connector, and measure the resistance between terminal No.2 and ground at the harness side.
OK: Continuity (Less than 2 ohms)
Q. Is the check result normal?
YES Go to Step 11.
NO Go to Step 9.
STEP 9. S-AWC control mode selector connector check: C-41
Q. Is the check result normal?
YES Go to Step 10.
NO Repair the defective connector. Then go to Step 13.
STEP 10. Check the wiring harness between C-41 S-AWC control mode selector connector terminal No.2 and body ground.
Check the ground line for open circuit.
Q. Is the check result normal?
YES Go to Step 11.
NO Repair the wiring harness. Then go to Step 13.
STEP 11. M.U.T.-III data list.
Check the following data list. (Refer to Data List Reference Table).
- Item 41: SW1 status (NORMAL)
- Item 42: SW2 status (OFF LOAD)
Q. Is the check result normal?
YES Go to Step 13.
NO Go to Step 12.
STEP 12. Retest the system.
Q. Is the check result normal?
YES Intermittent malfunction. How to Cope With Intermittent Malfunctions).
NO Replace the AWC-ECU. (Refer to AWC-ECU Removal and Installation). Then go to Step 13.
STEP 13. Retest the system.
Q. Is the check result normal?
YES This diagnosis is complete.
NO Return to Step 1.