DTC B2773, B2774, B2775, B2776

id080200802900

DTC

B2773

Driver‐side curtain air bag module circuit resistance low

B2774

Driver‐side curtain air bag module circuit resistance high

B2775

Driver‐side curtain air bag module circuit short to body ground

B2776

Driver‐side curtain air bag module circuit short to power supply
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.
•  Abnormal resistance (other than 1.4—3.2 ohms) detected in the driver-side curtain air bag module circuit
•  Malfunction in the wiring harness between the driver-side curtain air bag module and SAS unit
POSSIBLE CAUSE
•  Driver-side curtain air bag module connector malfunction
•  Open or short circuit in the wiring harness between the driver-side curtain air bag module and SAS unit
•  Driver-side curtain air bag module malfunction
•  SAS unit 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.
•  Turn the ignition switch to the LOCK position.
•  Disconnect the negative battery cable and wait for 1 min or more.
•  Remove the headliner.
•  Disconnect the driver-side curtain air bag module connector. (See CURTAIN AIR BAG MODULE REMOVAL/INSTALLATION.)
•  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 UNIT AND DRIVER-SIDE CURTAIN AIR BAG MODULE
•  Remove the column cover.
•  Disconnect the clock spring connector.
•  Remove the glove compartment.
•  Disconnect the passenger-side air bag module connector.
•  Disconnect the passenger-side curtain air bag module connectors.
•  Disconnect the driver and passenger-side side air bag module connectors.
•  Remove the rear door lower trim.
•  Disconnect the driver and passenger-side pre-tensioner seat belt connectors.
•  Partially peel back the floor covering.
•  Disconnect the SAS unit connector.
•  Inspect the wiring harnesses between SAS unit connector terminal 2Y and driver-side curtain air bag module connector terminal A, and SAS unit terminal 2V and driver-side curtain air bag module connector terminal B for the following:
―  Short to body ground
―  Open circuit
―  Short circuit between terminals
Note
•  Inspect for continuity while shaking the wiring harness between the SAS unit and driver-side curtain air bag module.
•  Is the wiring harness normal?
Yes
Go to the next step.
No
Replace the wiring harness between the SAS unit and the driver-side curtain air bag module.
3
INSPECT THE WIRING HARNESS BETWEEN THE SAS UNIT AND DRIVER-SIDE CURTAIN AIR BAG MODULE FOR A SHORT CIRCUIT TO THE POWER SUPPLY
•  Connect the negative battery cable.
•  Turn the ignition switch to the ON position with SAS unit connector and driver-side curtain air bag module connector disconnected.
•  Measure the voltage of SAS unit connector terminals 2Y and 2V of SAS unit harness side connector.
Note
•  Measure the voltage while shaking the wiring harness between the SAS unit and driver-side curtain air bag module.
•  Is the voltage measured?
Yes
Replace the wiring harness between the SAS unit and the driver-side curtain air bag module.
No
Go to the next step.
4
INSPECT DRIVER-SIDE CURTAIN AIR BAG MODULE
•  Turn the ignition switch to the LOCK position.
•  Disconnect the negative battery cable and wait for 1 min or more.
•  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.
•  Except for the driver-side curtain air bag module connector, reconnect all disconnected connectors.
•  Connect the negative battery cable.
•  Turn the ignition switch to the ON position.
•  Clear DTCs using the WDS or eguivalent. (See CLEARING DTC.)
•  Perform the DTC inspection for the SAS unit using the WDS or eguivalent. (See DTC DISPLAY.)
•  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.))
5
INSPECT DTCs
•  Turn the ignition switch to the LOCK position.
•  Disconnect the negative battery cable and wait for 1min 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.
•  Turn the ignition switch to the ON position.
•  Clear DTCs using the WDS or eguivalent. (See CLEARING DTC.)
•  Perform the DTC inspection for the SAS unit using the WDS or eguivalent. (See DTC DISPLAY.)
•  Are the same DTCs present?
Yes
Replace the SAS unit.
(See SAS UNIT REMOVAL/INSTALLATION.)
No
DTC troubleshooting completed.