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Pinpoint Test U: The SJB Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2011 Lincoln MKT. 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: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to BATTERY, BATTERY MOUNTING & BATTERY CABLES article.
  1. U1 CHECK THE SJB VOLTAGE SUPPLY CIRCUIT FOR AN OPEN 
    • Ignition ON.
      • NOTE: Measurements are taken with the fuses installed.
      Fig 1: Measuring Voltage Between SJB Fuse 5 (10A) Terminals And Ground
      G06075797Courtesy of FORD MOTOR CO.
    • Measure the voltage between the SJB fuse 5 (10A) and ground.
    • Is the voltage greater than 10 volts? 
    1. Yes  : GO to U2.
    2. No  : VERIFY the SJB fuse 5 (10A) is OK. If OK, GO to  U4. If not OK, REFER to the SYSTEM WIRING DIAGRAMS article to identify the possible causes of the circuit short.
  2. U2 CHECK THE SJB GROUND CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • Disconnect: Negative Battery Cable.
    • Disconnect: SJB C2280d.
    • Measure the resistance between the SJB C2280d-8, circuit GD133 (BK), harness side and ground; and between the SJB C2280d-12, circuit GD133 (BK), harness side and ground.
      Fig 2: Measuring Resistance Between SJB C2280D-8, Circuit GD133 (BK), Harness Side And Ground
      G06254422Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : GO to U3.
    2. No  : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
  3. U3 CHECK THE MS-CAN CIRCUITS BETWEEN THE SJB AND THE DLC FOR AN OPEN 
    • Disconnect: SJB C2280b.
    • Measure the resistance between the SJB C2280b-37, circuit VDB06 (GY/OG), harness side and the DLC C251-3, circuit VDB06 (GY/OG), harness side.
      Fig 3: Measuring Resistance Between SJB C2280B-37, Circuit VDB06 (GY/OG) And DLC C251-3, Circuit VDB06 (GY/OG)
      G06065465Courtesy of FORD MOTOR CO.
    • Measure the resistance between the SJB C2280b-38, circuit VDB07 (VT/OG), harness side and the DLC C251-11, circuit VDB07 (VT/OG), harness side.
      Fig 4: Measuring Resistance Between SJB C2280B-38 And DLC C251-11, Circuit VDB07 (VT/OG), Harness Side
      G06065466Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : CONNECT the negative battery cable. GO to U4.
    2. No  : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
  4. U4 CHECK FOR CORRECT SJB OPERATION 
    • Disconnect all the SJB connectors.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect all the SJB 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 SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES 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.
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