Diagnostic Procedure

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC B0004:11, B0004:12, B0004:13, B0004:19 OR B0004:1A [SAS CONTROL MODULE] DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	INSPECT DRIVER-SIDE KNEE 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 appropriate service information before handling the air bag system components. (See AIR BAG SYSTEM SERVICE WARNINGS [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) (See AIR BAG SYSTEM SERVICE CAUTIONS [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Switch the ignition off. Disconnect the negative battery terminal and wait for 1 min or more. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the driver-side knee air bag module connector. (See KNEE AIR BAG MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Inspect the driver-side knee air bag module connector (both sides of connector). (Corrosion, damage, and disconnected pins) Is there any malfunction of the driver-side knee air bag module connector (wiring harness-side)?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
1		No	Go to the next step.
2	INSPECT DRIVER-SIDE KNEE AIR BAG MODULE DEPLOYMENT SIGNAL CIRCUIT FOR SHORT TO GROUND Disconnect the passenger-side knee air bag module connectors. (See KNEE AIR BAG MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Disconnect the driver-side air bag module connectors. (See DRIVER-SIDE AIR BAG MODULE REMOVAL [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Disconnect the clock spring connectors. (See CLOCK SPRING REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Disconnect the passenger-side air bag module connectors. (See PASSENGER-SIDE AIR BAG MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Disconnect the driver and passenger-side front seat connectors. (See FRONT SEAT REMOVAL/INSTALLATION (US) .) Disconnect the driver and passenger-side curtain air bag module connectors. (See CURTAIN AIR BAG MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Disconnect the driver and passenger-side front pre-tensioner seat belt connectors. (See FRONT SEAT BELT REMOVAL/INSTALLATION .) Disconnect the all SAS control module connectors. (See SAS CONTROL MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .) Inspect the driver-side knee air bag module deployment signal circuit for a short to ground. (See CIRCUIT INSPECTION .) NOTE: Inspect for a short to ground while shaking the wiring harness between the SAS control module and driver-side knee air bag module. Is the circuit normal?	Yes	Go to the next step.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification.
3	INSPECT DRIVER-SIDE KNEE AIR BAG MODULE DEPLOYMENT SIGNAL CIRCUIT FOR OPEN CIRCUIT Driver-side knee air bag module and SAS control module connectors are disconnected. Inspect the driver-side knee air bag module deployment signal circuit for open circuit. (See CIRCUIT INSPECTION .) NOTE: Inspect for open circuit while shaking the wiring harness between the SAS control module and driver-side knee air bag module. Is the circuit normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT DRIVER-SIDE KNEE AIR BAG MODULE DEPLOYMENT SIGNAL CIRCUIT FOR SHORT TO EACH OTHER Driver-side knee air bag module and SAS control module connectors are disconnected. Inspect the driver-side knee air bag module deployment signal circuit for short to each other. (See CIRCUIT INSPECTION .) NOTE: Inspect for short to each other while shaking the wiring harness between the SAS control module and driver-side knee air bag module. Is the circuit normal?	Yes	Go to the next step.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT DRIVER-SIDE KNEE AIR BAG MODULE DEPLOYMENT SIGNAL CIRCUIT FOR SHORT TO OTHER AIR BAG MODULE CIRCUIT Driver-side knee air bag module and SAS control module connectors are disconnected. Other air bag module and pretensioner seat belt connectors are disconnected. Refer to the wiring diagram and inspect for continuity between the following terminals and other air bag module/pre-tensioner seat belt terminals (wiring harness-side). SAS control module terminal 1AI SAS control module terminal 1AE NOTE: Inspect for continuity while shaking the wiring harness between the SAS control module and driver-side knee air bag module. Is there continuity?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
5		No	Go to the next step.
6	INSPECT DRIVER-SIDE KNEE AIR BAG MODULE DEPLOYMENT SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY Driver-side knee air bag module and SAS control module connectors are disconnected. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Switch the ignition ON (engine off or on). Inspect the driver-side knee air bag module deployment signal circuit for a short to power supply. (See CIRCUIT INSPECTION .) NOTE: Inspect for a short to power supply while shaking the wiring harness between the SAS control module and driver-side knee air bag module. Is the circuit normal?	Yes	Go to the next step.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT DRIVER-SIDE KNEE AIR BAG MODULE Disconnect the negative battery terminal and wait for 1 min or more. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Connect the SAS control module connectors. Except for the driver-side knee air bag module connector, reconnect all disconnected connectors. Apply 2 ohms resistance to the driver-side knee air bag module terminals A and D (wiring harness-side). Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) 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 Pending DTCs present?	Yes	Go to the next step.
7		No	Replace the driver-side knee air bag module and perform the repair completion verification. (See KNEE AIR BAG MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .)
Repair completion verification	PERFORM SAS CONTROL MODULE DTC INSPECTION Switch the ignition off. Disconnect the negative battery terminal and wait for 1 min or more. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) Disconnect the 2 ohms resistance. Connect the driver-side knee air bag module connector. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .) 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 Pending DTCs present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW (US) .) If the CAN communication is normal, perform the diagnosis from Step 1. If the malfunction recurs, replace the SAS control module. (See SAS CONTROL MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM - US/CANADA SPEC.] .)
Repair completion verification		No	DTC troubleshooting completed.