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Home >> Mazda >> 2019 >> CX-9 Signature >> Repair and Diagnosis (Single Page) >> Restraints >> Air Bag, SRS >> On-Board Diagnostic - Airbag System (Two-Step Deployment Control System) >> DTC B00A0-09: Occupant Classification Sensor Internal Signal Output Unstable [SAS Control Module (Two-Step Deployment Control System)] >> Diagnostic Procedure
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Diagnostic Procedure

DTC B00A0:09 - SAS CONTROL MODULE (TWO-STEP DEPLOYMENT CONTROL SYSTEM) DIAGNOSTIC PROCEDURE

Step Inspection Action
1 INSPECT SEAT CUSHION
  • Inspect the seat cushion.
  • Is the seat cushion damp?
Yes Dry the seat cushion, then go to next step.
No Go to the next step.
2 INSPECT BATTERY
  • Inspect the battery terminals for looseness.
  • Inspect the battery. (See BATTERY INSPECTION .)
  • Is there any malfunction?
Yes Connect the battery terminals securely, and recharge or replace the battery. (See BATTERY RECHARGING .) (See BATTERY REMOVAL/INSTALLATION .)
Then go to the next step.
No Go to the next step.
3 PERFORM OCCUPANT CLASSIFICATION SENSOR CALIBRATION
Yes Go to the next step.
No DTC troubleshooting completed.
4 INSPECT OCCUPANT CLASSIFICATION SENSOR CONNECTOR
Yes Repair or replace the malfunctioning part, then go to Step 17.
No Go to the next step.
5 INSPECT OCCUPANT CLASSIFICATION SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
  • Occupant classification sensor connector is disconnected.
  • Inspect for continuity between the following terminal and body ground:
    • Passenger-side front seat connector (short cord-side) terminal 3A
NOTE:
  • Inspect for continuity while shaking the wiring harness between the passenger-side front seat connector and body ground.
  • 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 passenger-side front seat connector terminal and body ground.
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 17.

6 INSPECT OCCUPANT CLASSIFICATION SENSOR GROUND CIRCUIT FOR SHORT TO POWER SUPPLY
  • Occupant classification sensor connector is disconnected.
  • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminal:
    • Passenger-side front seat connector (short cord-side) terminal 3A
NOTE:
  • Measure the voltage while shaking the wiring harness between the passenger-side front seat connector and body ground.
  • 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 passenger-side front seat connector terminal and body ground.
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 17.

7 INSPECT OCCUPANT CLASSIFICATION SENSOR POWER SUPPLY CIRCUIT
  • Occupant classification sensor connector is disconnected.
  • Measure the voltage at the following terminal:
    • Passenger-side front seat connector (short cord-side) terminal 3B
NOTE:
  • Measure the voltage while shaking the wiring harness between the passenger-side front seat connector and body ground.
  • Is the voltage B+?
Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between passenger-side front seat connector terminal and IG1 relay. 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.
  • Replace the malfunctioning part. If there is no common connector:
  • Replace the wiring harness.

    Go to Step 17.

8 INSPECT PASSENGER-SIDE BUCKLE SWITCH OPERATION
  • Inspect the passenger-side buckle switch operation.
  • Does the passenger-side buckle switch operate normally?
Yes Go to Step 15.
No Go to the next step.
9 INSPECT PASSENGER-SIDE BUCKLE SWITCH
Yes Go to the next step.
No Replace the passenger-side buckle switch. (See FRONT BUCKLE REMOVAL/INSTALLATION .)
Then go to Step 17.
10 INSPECT PASSENGER-SIDE BUCKLE SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT
  • Passenger-side buckle switch connector is disconnected.
  • Inspect for continuity between the following terminal and body ground:
    • Passenger-side front seat connector (short cord-side) terminal 5A
NOTE:
  • Inspect for continuity while shaking the wiring harness between the passenger-side front seat connector and body ground.
  • 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 passenger-side front seat connector terminal and body ground.
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 17.

11 INSPECT PASSENGER-SIDE BUCKLE SWITCH GROUND CIRCUIT FOR SHORT TO POWER SUPPLY
  • Passenger-side buckle switch connector is disconnected.
  • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminal:
    • Passenger-side front seat connector (short cord-side) terminal 5A
NOTE:
  • Measure the voltage while shaking the wiring harness between the passenger-side front seat connector and body ground.
  • 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 passenger-side front seat connector terminal and body ground.
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 17.

12 INSPECT PASSENGER-SIDE BUCKLE SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND
NOTE:
  • Inspect for continuity while shaking the wiring harness between the SAS control module and passenger-side front seat connector.
  • Is there continuity?
Yes Refer to the wiring diagram and verify whether or not there is a common connector between passenger-side front seat connector terminal and SAS control 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 17.

No Go to the next step.
13 INSPECT PASSENGER-SIDE BUCKLE SWITCH SIGNAL CIRCUIT FOR OPEN CIRCUIT
  • Passenger-side buckle switch and SAS control module connectors are disconnected.
  • Inspect for continuity between the following terminals:
    • Passenger-side front seat connector (short cord-side) terminal 5B-SAS control module terminal 2T
NOTE:
  • Inspect for continuity while shaking the wiring harness between the SAS control module and passenger-side front seat connector.
  • 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 passenger-side front seat connector terminal and SAS control 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 17.

14 INSPECT PASSENGER-SIDE BUCKLE SWITCH SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
  • Passenger-side buckle switch and SAS control module connectors are disconnected.
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminal:
    • Passenger-side front seat connector (short cord-side) terminal 5B
NOTE:
  • Measure the voltage while shaking the wiring harness between the SAS control module and passenger-side front seat connector.
  • Is the voltage 0 V?
Yes Repair the passenger-side buckle switch connector. (Corrosion, damage, and disconnected pins)
Go to Step 17.
No Refer to the wiring diagram and verify whether or not there is a common connector between passenger-side front seat connector terminal and SAS control 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 17.

15 INSPECT PASSENGER-SIDE SEAT WARMER OPERATION
  • Inspect the passenger-side seat warmer operation.
  • Does the passenger-side seat warmer operate normally?
Yes Go to the next step.
No
  • Inspect the passenger-side seat warmer unit and seat warmer control unit connectors. (Corrosion, damage, and disconnected pins)
  • Inspect the passenger-side seat warmer units and seat warmer control unit. (See SEAT WARMER UNIT INSPECTION .) (See SEAT WARMER CONTROL UNIT INSPECTION .)
  • Refer to the wiring diagram and inspect the passenger-side seat warmer units body ground circuit.
  • Refer to the wiring diagram and inspect the seat warmer control unit power supply circuit.
  • Refer to the wiring diagram and inspect the seat warmer control unit body ground circuit.

    Repair or replace the malfunctioning part, then go to Step 17.

16 INSPECT PASSENGER-SIDE POWER SEAT OPERATION
  • Inspect the passenger-side power seat operation.
  • Does the passenger-side power seat operate normally?
Yes Go to the next step.
No
  • Inspect the passenger-side power seat switch and motor connectors. (Corrosion, damage, and disconnected pins)
  • Inspect the passenger-side power seat switch and motors. (See POWER SEAT SWITCH INSPECTION .) (See LIFT MOTOR INSPECTION .) (See SLIDE MOTOR INSPECTION .) (See RECLINER MOTOR INSPECTION .)
  • Refer to the wiring diagram and inspect the passenger-side power seat power supply circuit.
  • Refer to the wiring diagram and inspect the passenger-side power seat body ground circuit.

    Repair or replace the malfunctioning part, then go to the next step.

17 PERFORM DTC INSPECTION
Yes Replace the occupant classification sensor.
(See FRONT SEAT CUSHION TRIM REMOVAL/INSTALLATION .)
Go to the next step.
No DTC troubleshooting completed.
18 PERFORM SAS CONTROL MODULE DTC INSPECTION
Yes Replace the SAS control module.
(See SAS CONTROL MODULE REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM] .)
No DTC troubleshooting completed.