DTC 81

Side Air Bag Module (LH) (Squib) Circuit:

CIRCUIT OPERATION
- The SRS-ECU judges how severe a collision is by detecting signals from the left and right side impact sensors and the analog G-sensor. If the impact is over a predetermined level, the SRS-ECU outputs an ignition signal At this time, if the safing G-sensor is on, the SRS air bag will inflate.
- The ignition signal is input to the air bag module to inflate the air bag.




DTC SET CONDITIONS
- These DTC are output if communication between the side impact sensor (LH) and the SRS-ECU is not possible or communication is faulty.

TROUBLESHOOTING HINTS
- Damaged wiring harnesses or connectors
- Malfunction of the side impact sensor (LH)
- Malfunction of the SRS-ECU

DIAGNOSIS

Required Special Tool:
- MB991502: Scan Tool (MUT-II)
- MB991613: SRS Check Harness




STEP 1. Check the side air bag module line using the scan tool and MB991613 SRS Check harness.
1. Disconnect side air bag module (LH) connector D-15.
2. Connect special tool MB991613 connector (1).
3. Connect the negative battery terminal.
4. Erase DTC memory.

Q: Is any of DTC 81, 82, 85 or 86 output?

YES: Go to Step 2.

NO: Replace the seat back assembly of the front seat (LH). Refer to Front Seat. Then go to Step 3.







STEP 2. Check the harness wires between SRS-ECU connector C-74 and side air bag module (LH) connector D-15.

Q: Are the harness wires between SRS-ECU connector C-74 and side air bag module (LH) connector D-15 in good condition?

YES: Go to Step 3.

NO: Repair them. Then go to Step 3.

STEP 3. Check for DTC.

Q: Is any of DTC 81, 82, 85 or 86 output?

YES: Replace the SRS-ECU.

NO: This diagnosis is complete.(If no malfunctions are not found in all steps, an intermittent malfunction is suspected. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.)