Pinpoint Test Y: The DCSM Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, and 2011 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Remove restraint system diagnostic tools from the vehicle prior to road testing. If tools are not removed, the supplemental restraint system (SRS) device may not deploy in a crash. Failure to follow this instruction may result in serious personal injury or death in a crash and possibly violate vehicle safety standards.

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

NOTE: If a seat equipped with a Supplemental Restraint System (SRS) component is being serviced, the SRS must be depowered . Refer to SUPPLEMENTAL RESTRAINT SYSTEM -- FUSION, MILAN & MKZ article.

NOTE: The air bag warning lamp illuminates when the Restraints Control Module (RCM) fuse is removed and the ignition switch is ON. This is normal operation and does not indicate an SRS fault.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to BATTERY, MOUNTING & CABLES -- FUSION, MILAN & MKZ article.

Y1 VERIFY VEHICLE EQUIPMENT - SEAT SIDE AIR BAGS
- Inspect the vehicle for seat side air bags.
- Is the vehicle equipped with seat side air bags?
1. Yes : GO to Y2 .
2. No : GO to Y3.
Y2 CHECK THE DCSM VOLTAGE SUPPLY CIRCUITS FOR AN OPEN
- Ignition OFF.
- For vehicles with seat side air bags, carry out the following:
  - Depower the SRS. Refer to SUPPLEMENTAL RESTRAINT SYSTEM -- FUSION, MILAN & MKZ article.
  - Disconnect the driver seat side air bag module C3226.
  - Connect the restraint system diagnostic tool (418-133) to the driver seat side air bag module C3226.
  - Disconnect the passenger seat side air bag module C3227.
  - Connect the restraint system diagnostic tool (418-133) to the passenger seat side air bag module C3227.
  - Connect the negative battery cable.
- Disconnect: DCSM C3305a.
- Ignition ON.
- Measure the voltage between the DCSM C3305a-E, circuit SBB12 (GN/RD) harness side and ground; and between the DCSM C3305a-F, circuit SBB12 (GN/RD) harness side and ground.
  
  Fig 1: Measuring Voltage Between DCSM C3305a-E, Circuit SBB12 (GN/RD) And Ground
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
1. Yes : GO to Y4.
2. No : VERIFY the Battery Junction Box (BJB) fuse 12 (30A) is OK. If OK, REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool. If not OK, REFER to the SYSTEM WIRING DIAGRAMS article to identify the possible causes of the circuit short.
Y3 CHECK THE DCSM VOLTAGE SUPPLY CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: DCSM C3305a.
- Ignition ON.
- Measure the voltage between the DCSM C3305a-E, circuit SBB12 (GN/RD) harness side and ground; and between the DCSM C3305a-F, circuit SBB12 (GN/RD) harness side and ground.
  
  Fig 2: Measuring Voltage Between DCSM C3305a-E, Circuit SBB12 (GN/RD) And Ground
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
1. Yes : GO to Y4 .
2. No : VERIFY the Battery Junction Box (BJB) fuse 12 (30A) is OK. If OK, REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool. If not OK, REFER to the SYSTEM WIRING DIAGRAMS article to identify the possible causes of the circuit short.
Y4 CHECK THE DCSM GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the DCSM C3305a-M, circuit GD139 (BK/YE), harness side and ground.
  
  Fig 3: Measuring Resistance Between DCSM C33055a-M, Circuit GD139 (BK/YE), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
1. Yes : GO to Y5 .
2. No : REPAIR the circuit. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
Y5 CHECK THE MS-CAN CIRCUITS BETWEEN THE DCSM AND THE DLC FOR AN OPEN
- Disconnect: DCSM C3305c.
- Measure the resistance between the DCSM C3305c-1, circuit VDB06 (GY/OG), harness side and the Data Link Connector (DLC) C251-3, circuit VDB06 (GY/OG), harness side.
  
  Fig 4: Measuring Resistance Between DCSM C3305c-1 And Data Link Connector C251-3, Circuit VDB06 (GY/OG), Harness Side
  Courtesy of FORD MOTOR CO.
- Measure the resistance between the DCSM C3305c-2, circuit VDB07 (VT/OG), harness side and the DLC C251-11, circuit VDB07 (VT/OG), harness side.
  
  Fig 5: Measuring Resistance Between DCSM C3305c-2 And DLC C251-11, Circuit VDB07 (VT/OG), Harness Side
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
1. Yes : CONNECT the negative battery cable. GO to Y6 .
2. No : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
Y6 CHECK FOR CORRECT DCSM OPERATION
- Disconnect all the DCSM connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the DCSM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. Yes : INSTALL a new DCSM. REFER to SEAT SYSTEM - SEATS -- FUSION, MILAN & MKZ article. 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. CLEAR the DTCs. REPEAT the network test with the scan tool.