New Holland TRANS 106 – Transmission Control Unit (TRANS): C3-4 clutch solenoid or its wiring has failed open or shorted to ground

The transmission controller is unable to properly communicate with or actuate the C3-4 clutch solenoid due to an electrical interruption (open circuit) or an electrical short to the machine's chassis/ground.

• TG Series
• TG210
• TG230
• TG255
• TG285
• T8000 Series
• T9000 Series
• T9 Series
• Magnum Series
• MX Series

1. 1

   Visually inspect the wiring harness running from the transmission controller to the C3-4 clutch solenoid for chafed insulation, pinched wires, or broken connections.

2. 2

   Disconnect the harness at the C3-4 solenoid and the transmission controller to check for corroded, bent, or pushed-back pins.

3. 3

   Use a multimeter to test the wiring harness for continuity to rule out an open circuit, and test for continuity to ground to rule out a short to ground.

4. 4

   Measure the resistance (ohms) across the pins of the C3-4 clutch solenoid itself. If the resistance is infinite (open) or zero (shorted), the solenoid coil has failed internally.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the battery to prevent electrical spikes.

2. 2

   Repair Wiring

   If the diagnostic tests reveal a broken wire or a short to ground in the harness, repair the damaged section of the wiring or replace the harness segment.

3. 3

   Replace Solenoid

   If the wiring tests good but the solenoid fails the resistance test, remove the defective C3-4 clutch solenoid from the transmission valve body and install a new OEM solenoid. Ensure the mounting surface is clean and lubricate the new solenoid O-rings with clean transmission fluid before installation.

4. 4

   Reassemble and Clear Codes

   Reconnect the wiring harness and battery. Turn the key on and clear the inactive TRANS 106 fault code from the transmission controller.

5. 5

   Calibration

   After replacing a transmission clutch solenoid, you must perform a transmission clutch calibration procedure using the tractor's display or a diagnostic tool so the controller can learn the engagement characteristics of the new solenoid.