New Holland FAD – Central Controller (XCM) or Transmission Controller (TCU): Clutch D Solenoid Open Circuit Or Short To Ground

The transmission management system has detected an electrical fault—either a broken wire (open circuit), a disconnected plug, or a wire shorting to the chassis ground—in the circuit that energizes the Clutch D electro-hydraulic solenoid valve. When this code is active, the transmission controller will typically disable the affected clutch pack, which can result in a loss of specific gears, failure to shuttle shift, or an aborted transmission calibration.

• TM115
• TM120
• TM125
• TM130
• TM135
• TM140
• TM150
• TM155
• TM165
• TM175
• TM190
• T5
• T6
• T6010-T6070
• T7 Series
• TL70A
• TL80A
• TL90A
• TL100A
• MXM Series

1. 1

   Visually inspect the Clutch D solenoid connector (C025) on the transmission valve block and the central controller (XCM) connectors (C533 and C535) for corrosion, pushed pins, or moisture.

2. 2

   Perform a solenoid resistance test: Disconnect the Clutch D solenoid connector C025 and measure the resistance between terminal A and terminal B. It should be between 6 Ohms and 8 Ohms. If outside this range, the solenoid is internally faulty.

3. 3

   Perform a harness voltage/continuity test: If the solenoid tests okay, disconnect the central controller (XCM) connectors C533 and C535. Turn the keystart to the ON position and measure the voltage/continuity between the controller pins and the solenoid connector to isolate an open wire or short to ground.

1. 1

   Rectify the Circuit

   Based on the diagnostic tests, either repair the damaged section of the wiring harness, clean the C025 connector contacts, or replace the Clutch D solenoid valve on the transmission manifold.

2. 2

   Clear the Code

   Once the physical repair is made, use the tractor's instrument cluster or diagnostic tool to clear the stored FAD / 2066 error code from the Central Control Unit (CCU) EEPROM.

3. 3

   Test Operation

   Start the tractor and test the powershift/shuttle system for normal operation.

4. 4

   Recalibrate

   Because clutch faults often cause the system to abort calibration, you may need to perform a dynamic transmission calibration procedure to ensure the engagement pressures for Clutch D are relearned by the controller.