Diagnostic Procedure

WARNING: This page is about a different car, the 2015 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.

STEP 1. Scan tool CAN bus diagnostics
Using scan tool MB991958, diagnose the CAN bus lines.

Q: Is the check result normal?
1. YES: Go to Step 3.
2. NO: Repair the CAN bus lines. (Refer to TROUBLESHOOTING ). After repairing the CAN bus line, go to Step 2.
STEP 2. Retest the system.
Q: Is the check result normal?
1. YES: Intermittent malfunction. (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
2. NO: Go to Step 3.
STEP 3. Scan tool data list
Item No. 89: AWC switch (Refer to DATA LIST REFERENCE TABLE ).

Q: Is the check result normal?
1. YES: Go to Step 11.
2. NO: Go to Step 4.
STEP 4. AWC switch check.
Check the AWC switch. (Refer to AWC SWITCH CHECK ).

Q: Is the check result normal?
1. YES: Go to Step 5.
2. NO: Replace the AWC switch. (Refer to ELECTRIC PUMP RELAY ). Then go to Step 13.
STEP 5. Measure the voltage at C-50 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?
1. YES: Go to Step 8.
2. NO: Go to Step 6.
STEP 6. AWC switch connector, ETACS-ECU connector check: C-50, C-317
Q: Is the check result normal?
1. YES: Go to Step 7.
2. NO: Repair the defective connector. Then go to Step 13.
STEP 7. Check the wiring harness between C-50 AWC switch connector terminal No. 2 and C-317 ETACS-ECU connector terminal No. 5.
Check the power supply line for short or open circuit.

Q: Is the check result normal?
1. YES: Replace the ETACS-ECU. (Refer to ETACS-ECU ). Then go to Step 12.
2. NO: Check C-03 J/C (1). When no problem is found, repair the wiring harness. Then go to Step 13.
STEP 8. Voltage measurement at C-51 AWC-ECU connector
1. With C-51 AWC-ECU connector connected, measure the voltage between terminal No. 21 and ground at the harness side.
2. Turn the ignition switch to the "ON" position.
  OK: Battery voltage (Press and hold the AWC switch)
  
  OK: 1 V or less (Release the AWC switch)
Q: Is the check result normal?
1. YES: Go to Step 11.
2. NO: Go to Step 9.
STEP 9. Intermediate connector, AWC-ECU connector, AWC switch connector check: C-36, C-51, C-50
Q: Is the check result normal?
1. YES: Go to Step 10.
2. NO: Repair the defective connector. Then go to Step 13.
STEP 10. Wiring harness check between C-51 AWC-ECU connector terminal No. 21 and C-50 AWC switch connector terminal No. 1
Check the output line for short or open circuit.

Q: Is the check result normal?
1. YES: Go to Step 12.
2. NO: Repair the wiring harness. Then go to Step 11.
STEP 11. Scan tool data list
Combination meter item No. F13, F14, F15: Mode display (Refer to SERVICE DATA ).

Q: Is the check result normal?
1. YES: Go to Step 12.
2. NO: Replace the combination meter. (Refer to COMBINATION METER ). Then go to Step 12.
STEP 12. Retest the system.
Q: Is the check result normal?
1. YES: Intermittent malfunction. (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
2. NO: Replace the AWC-ECU. (Refer to AWC-ECU ). Then go to Step 13.
STEP 13. Retest the system.
Q: Is the check result normal?
1. YES: Return to Step 1.
2. NO: This diagnosis is complete.