DTC 86

Side-Airbag Module (LH) (Squib) System Fault Ground Circuit (Short-Circuited to Ground)

Side-Airbag 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. If the impact is over a predetermined level, the SRS-ECU outputs an ignition signal. At this time, if the side-airbag safing G-sensor is on, the SRS side-airbag will inflate.
- The ignition signal is input to the side-airbag module to inflate the side-airbag.

DTC SET CONDITIONS
This DTC is set if there is a short to the ground in the side-airbag module (LH) (squib) circuit.

TROUBLESHOOTING HINTS
- Damaged wiring harnesses or connectors
- Short to ground in the side-airbag module (LH) (squib) harness
- Malfunction of the SRS-ECU

DIAGNOSIS

Required Special Tools:
- MB991502: Scan Tool (MUT-II)
- MB991865: Dummy Resistor
- MB991866: Resistor Harness
- MB991223 (MB991222): Harness Set (Probe)

STEP 1. Check the side-airbag module (LH).




1. Disconnect the side-airbag module (LH) connector D-23.




2. Connect special tool MB991865 to special tool MB991866.

CAUTION: Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.

3. Insert special tool MB991866 into the D-23 harness side connector by backprobing.
4. Connect the negative battery terminal.
5. Erase the DTC memory, and then recheck the DTC.

Q: Is DTC 86 set?

YES: Go to Step 2.
NO: Replace the seatback assembly of the front seat (LH). (Refer to Front Seat Assembly.) Then go to Step 4

STEP 2. Check the side-airbag module (LH) circuit at the
SRS-ECU connector C-145.




1. Disconnect the SRS-ECU connector C-145.




2. Disconnect the side-airbag module (LH) connector D-23.

CAUTION: Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.




3. Check for continuity between the C-145 harness side connector terminals 21, 22 and body ground. It should be open circuit.

Q: Does continuity exist?

YES: Erase the DTC memory, and recheck if any DTC sets. If DTC 86 sets, replace the SRS-ECU. Then go to Step 4.
NO: Go to Step 3.







STEP 3. Check the harness Wires for short circuit to ground between the SRS-ECU connector C-145 (terminal No.21 and 22) and the side-airbag module (LH) connector D-23 (terminal No.1 and 2).

Q: Are the harness wires between the SRS-ECU connector C-145 (terminal No.21 and 22) and the side-airbag module (LH) connector D-23 (terminal No.1 and 2) in good condition?

YES: Go to Step 4.
NO: Repair the harness wires between the SRS-ECU connector C-145 and the side-airbag module (LH) connector D-23. Then go to Step 4.

STEP 4. Check the DTC.

Q: Is DTC 86 set?

YES: Return to Step 1.
NO: The procedure is complete. (If no malfunctions are not found in all steps, an intermittent malfunction is suspected. Refer to INTRODUCTION, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.)