Pinpoint Test F: The Occupant Classification System Module (OCSM) Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2008 Mercury Milan, 2008 Lincoln MKZ, and 2008 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Never probe the electrical connectors on safety belt buckle/retractor pretensioners or adaptive load limiting retractors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors, which increases the risk of serious personal injury or death.

NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

NOTE: The supplemental restraint system (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test.

F1 CHECK THE OCSM VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Key in OFF position.
- Depower the SRS. Refer to SUPPLEMENTAL RESTRAINT SYSTEM article.
- Disconnect: OCSM C3159
- Deactivate the SRS. Refer to SUPPLEMENTAL RESTRAINT SYSTEM article.
- Repower the SRS. Refer to SUPPLEMENTAL RESTRAINT SYSTEM article.
- Key in ON position.
- Measure the voltage between the OCSM C3159-1, circuit CBP24 (VT/GN), harness side and ground.
- Is the voltage greater than 10 volts?
1. YES : Go to F2.
2. NO : VERIFY the smart junction box (SJB) fuse 24 (7.5A) is OK. If OK, REPAIR the circuit. REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the network test with the scan tool.
F2 CHECK THE OCSM GROUND CIRCUIT FOR AN OPEN
- Key in OFF position.
- Measure the resistance between the OCSM C3159-14, circuit GD127 (BK/BU), harness side and ground.
- Is the resistance less than 5 ohms?
1. YES : Go to F3.
2. NO : REPAIR the circuit. REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the network test with the scan tool.
F3 CHECK THE HS-CAN CIRCUITS BETWEEN THE DATA LINK CONNECTOR (DLC) AND THE OCSM FOR AN OPEN
- Measure the resistance between the OCSM C3159-18, circuit VDB04 (WH/BU), harness side and the DLC C251-6, circuit VDB04 (WH/BU), harness side.
- Measure the resistance between the OCSM C3159-9, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
- Are the resistances less than 5 ohms?
1. YES : Go to F4.
2. NO : REPAIR the circuit. REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the network test with the scan tool.
F4 CHECK FOR CORRECT OCSM OPERATION
- Disconnect the OCSM connector.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect the OCSM connector and make sure it seats correctly.
- Verify the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new OCSM. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. REACTIVATE the SRS. CLEAR the DTCs. REPEAT the network test with the scan tool.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. REACTIVATE the SRS. REFER to SUPPLEMENTAL RESTRAINT SYSTEM article. CLEAR the DTCs. REPEAT the network test with the scan tool.