Pinpoint Test D: The Four-Wheel Drive (4WD) Control Module Does Not Respond To The Diagnostic Tool

WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

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

D1 CHECK THE HIGH SPEED CAN CIRCUITS BETWEEN THE 4WD CONTROL MODULE AND THE DLC FOR AN OPEN
- Key in OFF position.
- Disconnect: 4WD Control Module C3253.
- Measure the resistance between the 4WD control module C3253-4, circuit 1908 (WH), harness side and the DLC C251-6, circuit 1908 (WH), harness side; and between the 4WD control module C3253-12, circuit 1909 (BK), harness side and the DLC C251-14, circuit 1909 (BK), harness side.
  
  Fig 1: Checking High Speed CAN Circuits Between 4WD Control Module And DLC For An Open
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
Yes : GO to D2.

No : REPAIR the circuit in question. CONNECT the 4WD control module C3253. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the diagnostic tool data link test.
D2 CHECK FOR CORRECT 4WD CONTROL MODULE OPERATION
- Disconnect all the 4WD control module connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the 4WD control module connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes : For Escape, DIAGNOSE the high speed CAN. GO to PINPOINT TEST H .

For Escape - Hybrid, DIAGNOSE the high speed CAN. GO to PINPOINT TEST P .

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 self-test. CARRY OUT the diagnostic tool data link test.