DTC 79: Left Hand Side-airbag Module (Squib) System Fault 5 for Power Supply Circuit; DTC 93: Left Hand Side-airbag Module (Squib) System Fault 6 for Communication System: Diagnosis

Required Special Tools:

MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicle Communication Interface
- MB991827: MUT-III USB Cable
- MB991911: MUT-III Main Harness B

STEP 1. Check the side impact sensor (LH) (Using scan tool MB991958, read the diagnostic trouble code).
1. Disconnect the negative battery terminal.
2. Replace the side impact sensor (LH) with the side impact sensor (RH).
3. Connect the negative battery terminal.
4. Erase DTC memory, and then recheck the DTC.
Q: Is DTC 89 or 96 set?
1. YES: Replace the side impact sensor (LH) with a new one. Refer to SIDE IMPACT SENSOR . Then go to Step 3.
2. NO: Go to Step 2.
STEP 2. Check the harness wires for open circuit or short circuit between SRS-ECU connector C-74 (terminal No.34 and 36) and side impact sensor (LH) connector D-12 (terminal No.1 and 2).

Fig 1: Identifying SRS-ECU Connector C-74
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Fig 2: Identifying Side-Airbag Module Connector D-12 (LH)
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

Q: Are the harness wires between SRS-ECU connector C-74 (terminal No.34 and 36) and side impact sensor (LH) connector D-12 (terminal No.1 and 2) in good condition?
1. YES: Erase the DTC memory, and recheck if any DTC sets. If DTC 79 or 93 sets, replace the SRS-ECU. Refer to HARNESS CONNECTOR . Then go to Step 3.
2. NO: Repair the harness wires between SRS-ECU connector C-74 and side impact sensor (LH) connector D-12. Then go to Step 3.
STEP 3. Recheck for diagnostic trouble code.
Q: Is DTC 79 set?
1. YES: Return to Step 1.
2. NO: The procedure is complete (If no malfunctions are found in all steps, an intermittent malfunction is suspected. Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTIONS ).