LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2022 >> Transit Connect Titanium, Gas/Ethanol >> Repair and Diagnosis >> External Pages >> Different car >> Section 580 (Rear Drive Axle/Differential - Vehicles With: Ford 9.75 Inch Ring Gear) >> Diagnosis And Testing >> Electronic Locking Differential (ELD) >> Pinpoint Tests >> Pinpoint Test B: P185D: 00

Pinpoint Test B: P185D: 00

WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
  1. Refer to Wiring Diagrams Two Wheel Drive/Four Wheel Drive Systems for schematic and connector information.

    Normal Operation and Fault Conditions 

    When the ELD is fully locked, the indicator illuminates steadily. When the ELDMSS is engaged to lock the rear differential, a PWM signal is sent to the ELD field coil by the TCCM through the differential lock control circuit. This PWM signal is initially 98% duty cycle to lock the differential and then tapers off to a lower duty cycle once the differential is locked. If the differential does not lock, the TCCM module continues to send the signal for a set amount of time. Once the ELD is locked, the indicator illuminates steadily.

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    TCCM P185D: 00 Differential Lock-Up Control Circuit Performance: No Sub Type Information The TCCM sends a signal to the lock up solenoid to lock the differential. After several unsuccessful attempts, the TCCM sets this DTC alerting the driver the ELD is inoperative. Fault may be due to a wheel speed condition or due to a mechanical failure within the driveline / axle subsystem.

    Possible Sources 

    • Wiring, terminals or connectors
    • ELD field coil

  2. B1 CHECK THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE WHEEL SPEED SENSOR PID (PARAMETER IDENTIFICATION)S

    NOTE: Make sure the battery is fully charged before carrying out this pinpoint test.

    • Enter the following diagnostic mode on the scan tool: ABS Module Datalogger

    • While driving the vehicle at 30 km/h (18 mph), monitor the following wheel speed sensor PIDs:

      • Left Front Wheel Speed Sensor (LF_WSPD)

      • Left Rear Wheel Speed Sensor (LR_WSPD)

      • Right Front Wheel Speed Sensor (RF_WSPD)

      • Right Rear Wheel Speed Sensor (RR_WSPD)

    • Compare the speedometer reading to the wheel speed sensor PIDs.

    Do the wheel speed sensor PIDs and speedometer speeds match within 1.5 km/h (1 mph)? 

    Yes  GO to  B2
    No  VERIFY that the 4 road wheels are the same size and have similar tread depth. CHECK the ABS for faults.

  3. B2 CHECK RESISTANCE OF THE ELD (ELECTRONIC LOCKING DIFFERENTIAL) FIELD COIL

    • Ignition OFF.

    • Disconnect ELD field coil.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      ELD field coil pin 1 component side
      GFD551830Courtesy of FORD MOTOR COMPANY
      		 ELD field coil pin 2 component side

    Is the resistance between 2-4 ohms? 

    Yes  GO to  B3
    No  INSTALL a new ELD field coil. REFER to: Differential Carrier - Vehicles With: Electronic Locking Differential (ELD) . REFER to: Differential Carrier - Vehicles With: Electronic Locking Differential (ELD) .

  4. B3 CHECK THE ELD (ELECTRONIC LOCKING DIFFERENTIAL) FIELD COIL GROUND

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      ELD field coil pin 2 component side
      GFD551830Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance less than 3 ohms? 

    Yes  To repair the rear differential, REFER to: Differential Carrier - Vehicles With: Electronic Locking Differential (ELD) . . CLEAR the DTCs.
    No  REPAIR the circuit.
scientia non olet · About LEMON Manuals