Pinpoint Test H: The 4X4 Control Module 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.

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, MOUNTING & CABLES -- FUSION, MILAN & MKZ article.

H1 CHECK THE 4X4 CONTROL MODULE VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: 4X4 Control Module C3253.
- Ignition ON.
- Measure the voltage between the 4X4 control module C3253-4, circuit CBP35 (YE/GY), harness side and ground; and between the 4X4 control module C3253-5, circuit SBP11 (BU/RD), harness side and ground.
  
  Fig 1: Measuring Voltage Between 4X4 Control Module C3253-4, Circuit CBP35 (YE/GY), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
1. Yes : GO to H2 .
2. No : VERIFY the Smart Junction Box (SJB) fuse 11 (10A) or 35 (10A) is OK. If OK, REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
H2 CHECK THE 4X4 CONTROL MODULE GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the 4X4 control module C3253-15, circuit GD126 (BK/WH), harness side and ground.
  
  Fig 2: Measuring Resistance Between 4X4 Control Module C3253-15, Circuit GD126 (BK/WH) And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
1. Yes : GO to H3 .
2. No : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
H3 CHECK THE HS-CAN CIRCUITS BETWEEN THE 4X4 CONTROL MODULE AND THE DLC FOR AN OPEN
- Measure the resistance between the 4X4 control module C3253-3, circuit VDB04 (WH/BU), harness side and the Data Link Connector (DLC) C251-6, circuit VDB04 (WH/BU), harness side.
  
  Fig 3: Measuring Resistance Between 4X4 Control Module C3253-3 And Data Link Connector (DLC) C251-6, Circuit VDB04 (WH/BU), Harness Side
  Courtesy of FORD MOTOR CO.
- Measure the resistance between the 4X4 control module C3253-11, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
  
  Fig 4: Measuring Resistance Between 4X4 Control Module C3253-11 And DLC C251-14, Circuit VDB05 (WH), Harness Side
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
1. Yes : CONNECT the negative battery cable. GO to H4 .
2. No : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
H4 CHECK FOR CORRECT 4X4 CONTROL MODULE OPERATION
- Disconnect the 4X4 control module connector.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect the 4X4 control module connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. Yes : INSTALL a new 4X4 control module. REFER to FOUR WHEEL DRIVE (4WD) SYSTEMS -- 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.