DTC B1128:1C

id080200825600

System Malfunction Location

• Diagnostic circuit voltage malfunction in driver-side curtain air bag module

Detection Condition

Warning

• Detection conditions are for understanding the DTC outline before performing an inspection. Performing an inspection according to only the detection conditions may cause injury due to an operating error, or damage the system. When performing an inspection, always follow the inspection procedure.

• Diagnostic circuit voltage malfunction in driver-side curtain air bag module

Possible Causes

• Driver-side curtain air bag module connector malfunction

• Short to body ground or spontaneous short to power supply in wiring harness between driver-side curtain air bag module and SAS control module

• SAS control module malfunction

System Wiring Diagram

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Diagnostic Procedure

Step

Inspection

Action

1

INSPECT DRIVER-SIDE CURTAIN AIR BAG MODULE CONNECTOR

Warning

•  Handling the component parts improperly can accidentally operate (deploy) the air bag module, which may seriously injure you. Read the service warnings/cautions and the workshop manual before handling the air bag system components.
(See AIR BAG SYSTEM SERVICE WARNINGS.)

(See AIR BAG SYSTEM SERVICE CAUTIONS.)

•  Switch the ignition to off.

•  Disconnect the negative battery cable and wait for 1 min or more.

•  Remove the Headliner. (See HEADLINER REMOVAL/INSTALLATION.) (See HEADLINER REMOVAL/INSTALLATION [3HB].)

•  Disconnect the driver-side curtain air bag module connector. (See CURTAIN AIR BAG MODULE REMOVAL/INSTALLATION.)

•  Inspect the driver-side curtain air bag module connector. (Corrosion, damage, and disconnected pins)

•  Is there any malfunction of the driver-side curtain air bag module connector?

Yes

Replace the driver-side curtain air bag module wiring harness.

No

Go to the next step.

2

INSPECT WIRING HARNESS BETWEEN SAS CONTROL MODULE AND DRIVER-SIDE CURTAIN AIR BAG MODULE FOR SHORT TO BODY GROUND

•  Remove the column cover.
(See COLUMN COVER REMOVAL/INSTALLATION.)

•  Disconnect the clock spring connector.

•  Remove the glove compartment cover.
(See GLOVE COMPARTMENT COVER REMOVAL/INSTALLATION.)

•  Disconnect the passenger-side air bag module connector.

•  Disconnect the driver and passenger-side side air bag module connectors.

•  Disconnect the passenger-side curtain air bag module connector.

•  Disconnect the driver and passenger-side pre-tensioner seat belt connectors.

•  Remove the rear console. (See REAR CONSOLE REMOVAL/INSTALLATION.)

•  Disconnect the SAS control module connectors.

•  Inspect for a continuity between SAS control module connector terminal 1K and body ground, SAS control module connector terminal 1I and body ground.

Note

•  Inspect for continuity while shaking the wiring harness between the SAS control module and the driver-side curtain air bag module.

•  Is there continuity?

Yes

Replace the wiring harness between the SAS control module and the driver-side curtain air bag module.

No

Go to the next step.

3

INSPECT THE WIRING HARNESS BETWEEN THE SAS CONTROL MODULE AND DRIVER-SIDE CURTAIN AIR BAG MODULE FOR A SHORT CIRCUIT TO THE POWER SUPPLY

•  Connect the negative battery cable.

•  Switch the ignition to ON with SAS control module connector and driver-side curtain air bag module connector disconnected.

•  Measure the voltage of SAS control module connector terminals 1K and 1I.

Note

•  Measure the voltage while shaking the wiring harness between the SAS control module and driver-side curtain air bag module.

•  Is the voltage measured?

Yes

Replace the wiring harness between the SAS control module and the driver-side curtain air bag module.

No

Go to the next step.

4

PERFORM SAS CONTROL MODULE DTC INSPECTION

•  Switch the ignition to off.

•  Disconnect the negative battery cable and wait for 1 min or more.

•  Reconnect all disconnected connectors.

•  Connect the negative battery cable.

•  Switch the ignition to ON.

•  Clear the DTC for the SAS control module using the M-MDS.
(See CLEARING DTC.)

•  Perform the DTC inspection for the SAS control module using the M-MDS.
(See DTC DISPLAY.)

•  Are the same DTCs present?

Yes

Replace the SAS control module.

(See SAS CONTROL MODULE REMOVAL/INSTALLATION.)

No

DTC troubleshooting completed.

Step	Inspection		Action
1	INSPECT DRIVER-SIDE CURTAIN AIR BAG MODULE CONNECTOR Warning • Handling the component parts improperly can accidentally operate (deploy) the air bag module, which may seriously injure you. Read the service warnings/cautions and the workshop manual before handling the air bag system components. (See AIR BAG SYSTEM SERVICE WARNINGS.) (See AIR BAG SYSTEM SERVICE CAUTIONS.) • Switch the ignition to off. • Disconnect the negative battery cable and wait for 1 min or more. • Remove the Headliner. (See HEADLINER REMOVAL/INSTALLATION.) (See HEADLINER REMOVAL/INSTALLATION [3HB].) • Disconnect the driver-side curtain air bag module connector. (See CURTAIN AIR BAG MODULE REMOVAL/INSTALLATION.) • Inspect the driver-side curtain air bag module connector. (Corrosion, damage, and disconnected pins) • Is there any malfunction of the driver-side curtain air bag module connector?	Yes	Replace the driver-side curtain air bag module wiring harness.
1		No	Go to the next step.
2	INSPECT WIRING HARNESS BETWEEN SAS CONTROL MODULE AND DRIVER-SIDE CURTAIN AIR BAG MODULE FOR SHORT TO BODY GROUND • Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION.) • Disconnect the clock spring connector. • Remove the glove compartment cover. (See GLOVE COMPARTMENT COVER REMOVAL/INSTALLATION.) • Disconnect the passenger-side air bag module connector. • Disconnect the driver and passenger-side side air bag module connectors. • Disconnect the passenger-side curtain air bag module connector. • Disconnect the driver and passenger-side pre-tensioner seat belt connectors. • Remove the rear console. (See REAR CONSOLE REMOVAL/INSTALLATION.) • Disconnect the SAS control module connectors. • Inspect for a continuity between SAS control module connector terminal 1K and body ground, SAS control module connector terminal 1I and body ground. Note • Inspect for continuity while shaking the wiring harness between the SAS control module and the driver-side curtain air bag module. • Is there continuity?	Yes	Replace the wiring harness between the SAS control module and the driver-side curtain air bag module.
2		No	Go to the next step.
3	INSPECT THE WIRING HARNESS BETWEEN THE SAS CONTROL MODULE AND DRIVER-SIDE CURTAIN AIR BAG MODULE FOR A SHORT CIRCUIT TO THE POWER SUPPLY • Connect the negative battery cable. • Switch the ignition to ON with SAS control module connector and driver-side curtain air bag module connector disconnected. • Measure the voltage of SAS control module connector terminals 1K and 1I. Note • Measure the voltage while shaking the wiring harness between the SAS control module and driver-side curtain air bag module. • Is the voltage measured?	Yes	Replace the wiring harness between the SAS control module and the driver-side curtain air bag module.
3		No	Go to the next step.
4	PERFORM SAS CONTROL MODULE DTC INSPECTION • Switch the ignition to off. • Disconnect the negative battery cable and wait for 1 min or more. • Reconnect all disconnected connectors. • Connect the negative battery cable. • Switch the ignition to ON. • Clear the DTC for the SAS control module using the M-MDS. (See CLEARING DTC.) • Perform the DTC inspection for the SAS control module using the M-MDS. (See DTC DISPLAY.) • Are the same DTCs present?	Yes	Replace the SAS control module. (See SAS CONTROL MODULE REMOVAL/INSTALLATION.)
4		No	DTC troubleshooting completed.