Without Steering Audio Remote Switch
INSPECTION PROCEDURE 2: Mode does not change even when the AWC switch is pressed [Vehicles without steering wheel audio remote control switch]
POWER SUPPLY SYSTEM CIRCUIT
Refer to C2100.
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.
COMMENTS ON TROUBLE SYMPTOM
AWC switch or AWC-ECU may have a problem.
PROBABLE CAUSES
- AWC switch malfunction
- Malfunction of the combination meter
- Damaged harness wires and connectors
- Malfunction of AWC-ECU
DIAGNOSTIC PROCEDURE
STEP 1. Scan tool CAN bus diagnostics
Using scan tool MB991958, diagnose the CAN bus lines.
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. Scan tool service data
Item No. 90, 91: AWC switch (Refer to service data reference table Data List Reference Table.)
Q. Is the check result normal?
YES Go to Step 11.
NO Go to Step 4.
STEP 4. AWC switch single unit check
Check the AWC switch.(Refer to Testing and Inspection.)
Q. Is the check result normal?
YES Go to Step 5.
NO Replace the AWC switch.(Refer to Service and Repair.) Then go to Step 13.
STEP 5. Measure the voltage at C-214 AWC switch connector.
(1)Disconnect the connector, and measure the voltage between terminal No.2 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 9.
NO Go to Step 6.
STEP 6. Voltage measurement at C-46 AWC-ECU connector
(1)With C-46 AWC-ECU connector connected, measure the voltage between terminal No. 11 and ground at the harness side.
(2)Turn the ignition switch to the "ON" position.
OK: battery voltage
Q. Is the check result normal?
YES Go to Step 7.
NO Go to Step 12.
STEP 7. AWC-ECU connector, intermediate connector, clock spring connector, AWC switch connector check: C-46, C-31, C-42, C-202, C-205, C-214
Q. Is the check result normal?
YES Go to Step 8.
NO Repair the defective connector. Then go to Step 13.
STEP 8. Wiring harness check between C-46 AWC-ECU connector terminal No. 11 and C-214 AWC switch connector terminal No. 2
Check the wiring harness for open or short circuit (short to ground).
Q. Is the check result normal?
YES Go to Step 12.
NO Repair the wiring harness. Then go to Step 13.
STEP 9. AWC-ECU connector, intermediate connector, clock spring connector, AWC switch connector check: C-46, C-31, C-42, C-202, C-205, C-214
Q. Is the check result normal?
YES Go to Step 10.
NO Repair the defective connector. Then go to Step 13.
STEP 10. Wiring harness check between C-46 AWC-ECU connector terminal No. 19 and C-214 AWC switch connector terminal No. 4
Check the wiring harness 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. Scan tool service data
Combination meter item No. F13, F14, F15: Mode display Data List Reference Table.)
Q. Is the check result normal?
YES Go to Step 12.
NO Replace the combination meter. Removal and Replacement.) Then 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 Active Center Differential (ACD).) Then go to Step 13.
STEP 13. Retest the system.
Q. Is the check result normal?
YES Return to Step 1.
NO This diagnosis is complete.