LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lincoln >> 2000 >> Town Car Signature >> Repair and Diagnosis >> External Pages >> Different car >> Section 1049 (Module Communications Network System) >> Diagnostic Tests >> Communications Network - Hybrid >> Pinpoint Tests >> Pinpoint Test M: The Four Wheel Drive (4WD) Control Module Does Not Respond To The Scan Tool >> Pinpoint Test M: The Four Wheel Drive (4WD) Control Module Does Not Respond To The Scan Tool
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Pinpoint Test M: The Four Wheel Drive (4WD) Control Module Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 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.
  1. M1 CHECK VOLTAGE TO THE 4WD CONTROL MODULE 
    • Key in OFF position.
    • Disconnect: 4WD Control Module C3253
    • Key in ON position.
      • Fig 1: Checking Circuit For Voltage
      GF0025441Courtesy of FORD MOTOR CO.
    • Measure the voltage between the 4WD control module C3253-6, circuit 704 (DG/LG), harness side and ground; and between the 4WD control module C3253-5, circuit 1003 (GY/YE), harness side and ground.
    • Are the voltages greater than 10 volts? 
    1. YES  : Go to  M2.
    2. NO  : VERIFY the smart junction box (SJB) fuse 18 (10A) or 35 (5A) is OK. If OK, REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
  2. M2 CHECK THE 4WD CONTROL MODULE GROUND 
    • Key in OFF position.
      • Fig 2: Checking Circuit For Open
      GF0025447Courtesy of FORD MOTOR CO.
    • Measure the resistance between the 4WD control module C3253-15, circuit 57 (BK), harness side and ground.
    • Is the resistance less than 5 ohms? 
    1. YES  : Go to  M3.
    2. NO  : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  3. M3 CHECK THE HS-CAN CIRCUITS BETWEEN THE 4WD CONTROL MODULE AND THE DATA LINK CONNECTOR (DLC) FOR AN OPEN 
      Fig 3: Checking Circuit For Open
      GF0026041Courtesy of FORD MOTOR CO.
    • 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.
    • Are the resistances less than 5 ohms? 
    1. YES  : Go to  M4.
    2. NO  : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
  4. M4 CHECK FOR CORRECT 4WD CONTROL MODULE OPERATION 
    • Disconnect the 4WD control module connector.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect the 4WD 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 4WD control module. REFER to FOUR WHEEL DRIVE (4WD) SYSTEMS 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.
scientia non olet · About LEMON Manuals