DTC B1128:11/B1128:12/B1128:13/B1128:19/B1128:1A

id080200821600

System malfunction location	•  B1128:11: Driver-side curtain air bag module circuit short to body ground •  B1128:12: Driver-side curtain air bag module circuit short to power supply •  B1128:13: Driver-side curtain air bag module circuit open circuit or resistance high •  B1128:19: Short circuit to driver-side curtain air bag module and other air bag module circuits •  B1128:1A: Driver-side curtain air bag module circuit resistance low
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. •  Resistance other than 0.81—6.42 ohms detected in driver-side curtain air bag module circuit •  Wiring harness between the driver-side curtain air bag module and SAS control module has a malfunction
Fail-safe function	Not applicable
Possible cause	•  Driver-side curtain air bag module connector malfunction •  Short circuit to power supply or body ground in the wiring harness between the driver-side curtain air bag module and SAS control module •  Open circuit in the wiring harness between the driver-side curtain air bag module and SAS control module •  Driver-side curtain air bag module malfunction •  SAS control module malfunction

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 off. •  Disconnect the negative battery cable and wait for 1 min or more. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) •  Remove the headliner. (See HEADLINER REMOVAL/INSTALLATION.) •  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 malfunctioning part, then go to Step 6.
		No	Go to the next step.
2	INSPECT DRIVER-SIDE CURTAIN AIR BAG MODULE CIRCUIT FOR SHORT TO GROUND •  Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION.) •  Disconnect the clock spring connector. (See CLOCK SPRING REMOVAL/INSTALLATION.) •  Remove the glove compartment. (See GLOVE COMPARTMENT REMOVAL/INSTALLATION.) •  Disconnect the passenger-side air bag module connector. (See PASSENGER-SIDE AIR BAG MODULE REMOVAL.) •  Disconnect the driver and passenger-side front seat connector. (See FRONT SEAT REMOVAL/INSTALLATION.) •  Disconnect the driver and passenger-side pre-tensioner seat belt connectors. (See FRONT SEAT BELT REMOVAL/INSTALLATION.) •  Disconnect the passenger-side curtain air bag module connector. (See CURTAIN AIR BAG MODULE REMOVAL/INSTALLATION.) •  Disconnect the all SAS control module connectors. (See SAS CONTROL MODULE REMOVAL/INSTALLATION.) •  Inspect for continuity between the following terminals (wiring harness-side) and body ground: ―  SAS control module terminal 1S (Type A)/1G (Type B) ―  SAS control module terminal 1V (Type A)/1C (Type B) 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	Refer to the wiring diagram and verify whether or not there is a common connector between SAS control module terminal and driver-side curtain air bag module terminal. If there is a common connector: •  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. •  Replace the malfunctioning part. If there is no common connector: •  Replace the wiring harness which has a short to ground. Go to Step 6.
		No	Go to the next step.
3	INSPECT DRIVER-SIDE CURTAIN AIR BAG MODULE CIRCUIT FOR OPEN CIRCUIT •  Driver-side curtain air bag module and SAS control module connectors are disconnected. •  Inspect for continuity between the following terminals (wiring harness-side): ―  Driver-side curtain air bag module terminal A—SAS control module terminal 1S (Type A)/1G (Type B) ―  Driver-side curtain air bag module terminal B—SAS control module terminal 1V (Type A)/1C (Type B) Note •  Inspect for continuity while shaking the wiring harness between the SAS control module and driver-side curtain air bag module. •  Is there continuity?	Yes	Go to the next step.
		No	Refer to the wiring diagram and verify whether or not there is a common connector between SAS control module terminal and driver-side curtain air bag module terminal. If there is a common connector: •  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. •  Replace the malfunctioning part. If there is no common connector: •  Replace the wiring harness which has an open circuit. Go to Step 6.
4	INSPECT DRIVER-SIDE CURTAIN AIR BAG MODULE CIRCUIT FOR SHORT TO POWER SUPPLY •  Driver-side curtain air bag module and SAS control module connectors are disconnected. •  Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) •  Switch the ignition ON (engine off or on). •  Measure the voltage at the following terminals (wiring harness-side): ―  SAS control module terminal 1S (Type A)/1G (Type B) ―  SAS control module terminal 1V (Type A)/1C (Type B) Note •  Measure the voltage while shaking the wiring harness between the SAS control module and driver-side curtain air bag module. •  Is the voltage 0 V?	Yes	Go to the next step.
		No	Refer to the wiring diagram and verify whether or not there is a common connector between SAS control module terminal and driver-side curtain air bag module terminal. If there is a common connector: •  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. •  Replace the malfunctioning part. If there is no common connector: •  Replace the wiring harness which has a short to power supply. Go to Step 6.
5	INSPECT DRIVER-SIDE CURTAIN AIR BAG MODULE •  Switch the ignition off. •  Disconnect the negative battery cable and wait for 1 min or more. •  Connect the SAS control module connectors. •  Except for the driver-side curtain air bag module connector, reconnect all disconnected connectors. •  Connect the SST (Fuel and thermometer checker) or apply 2 ohms resistance to the driver-side curtain air bag module connector terminals A and B. •  Set the SST (Fuel and thermometer checker) to 2 ohms. •  Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) •  Switch the ignition ON (engine off or 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 INSPECTION.) •  Are the same DTCs present?	Yes	Go to the next step.
		No	Replace the driver-side curtain air bag module. (See CURTAIN AIR BAG MODULE REMOVAL/INSTALLATION.) Then go to the next step.
6	PERFORM SAS CONTROL MODULE DTC INSPECTION •  Switch the ignition off. •  Disconnect the negative battery cable and wait for 1 min or more. •  Disconnect the SST (Fuel and thermometer checker) or the 2 ohms resistance. •  Connect the driver-side curtain air bag module connector. •  Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) •  Switch the ignition ON (engine off or 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 INSPECTION.) •  Are the same DTCs present?	Yes	Replace the SAS control module. (See SAS CONTROL MODULE REMOVAL/INSTALLATION.)
		No	DTC troubleshooting completed.