Pinpoint Test E: The OCSM Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2013 Lincoln MKX and 2013 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

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.

NOTE: Failure to disconnect the battery when instructed results in false resistance readings. Refer to BATTERY, MOUNTING AND CABLES .

E1 CHECK THE OCSM VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Ignition OFF.
- Wait one minute.
- Disconnect: OCSM C3159.
- Ignition ON.
- Measure the voltage between the OCSM C3159-1, circuit CBP41 (BU), harness side and ground.
  
  Fig 1: Measuring Voltage Between OCSM C3159-1, Circuit CBP41 (BU), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
  - YES : GO to E2.
  - No : VERIFY the Body Control Module (BCM) fuse 41 (7.5A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the appropriate SYSTEM WIRING DIAGRAMS (Edge) article or SYSTEM WIRING DIAGRAMS (MKX) article to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the network test with the scan tool.
E2 CHECK THE OCSM GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the OCSM C3159-14, circuit GD143 (BK/VT), harness side and ground.
  
  Fig 2: Measuring Resistance Between OCSM C3159-14, Circuit GD143 (BK/VT), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
  - YES : GO to E3.
  - No : REPAIR the circuit. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
E3 CHECK THE HS-CAN CIRCUITS BETWEEN THE OCSM AND THE DATA LINK CONNECTOR (DLC) 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.
  
  Fig 3: Measuring Resistance Between OCSM C3159-18, Circuit VDB04 (WH/BU) And DLC C251-6, Circuit VDB04 (WH/BU), Harness Side
  Courtesy of FORD MOTOR CO.
- Measure the resistance between the OCSM C3159-9, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
  
  Fig 4: Measuring Resistance Between OCSM C3159-9, Circuit VDB05 (WH) And DLC C251-14, Circuit VDB05 (WH), Harness Side
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
  - YES : CONNECT the negative battery cable. GO to E4.
  - No : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
E4 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?
  - YES : INSTALL a new OCSM. CLEAR the DTCs. REPEAT the network test with the scan tool.
  - No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.