Code No.75: Side-airbag module (squib) (RH) system (short-circuited to the power supply)

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.

DIAGNOSIS CODE SET CONDITIONS

This diagnosis code is set if the side-airbag squib (RH) wire(s) are short-circuited to the power supply.

PROBABLE CAUSES

Damaged wiring harnesses or connectors
Short to the power supply in the side-airbag module (RH) (squib) harness
Malfunction of the SRS-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check the diagnosis code by connecting a dummy resistor (M.U.T.-III diagnosis code).

(1)Disconnect the negative battery terminal.

(2)Disconnect the side-airbag module (RH) connector D-29.

(3)Connect special tool dummy resistor (MB991865) to special tool resistor harness (MB991866).
(4)

caution

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

Insert special tool (MB991866) into the D-29 harness side connector by backprobing.
(5)Connect the negative battery terminal.
(6)Erase the diagnosis code memory, and check the diagnosis code.

Q. Is diagnosis code 75 set?

Go to Step 2.

Replace the frame assembly (Refer to GROUP 52A, Front Seat

STEP 2. Voltage measurement at the SRS-ECU connector C-146.

(1)Disconnect SRS-ECU connector C-146.

(2)

danger

To prevents the air bag from deploying unintentionally, disconnect the side-airbag module (RH) connector D-29 to short the squib circuit.

Disconnect side-airbag module (RH) connector D-29.
(3)Turn the ignition switch to the "ON" position.

(4)

caution

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

Voltage measurement between C-146 harness side connector terminals 23 and 24 and body earth.
OK: 0 V

Q. Is the check result normal?

Go to Step 3.

Repair the harness wires between SRS-ECU connector C-146 (terminal No.23 and 24) and side-airbag module (RH) connector D-29 (terminal No.1 and 2).

STEP 3. Check whether the diagnosis code is reset.

Q. Is diagnosis code 75 set?

	Replace the SRS-ECU (Refer to ).

	An intermittent malfunction is suspected (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points ).