New Holland 2349 – TCM: High Range Clutch Solenoid Circuit Fault

The Transmission Control Module (TCM) has detected an electrical fault in the high range clutch solenoid circuit. This can manifest as an open circuit, a short to ground, or an excess voltage condition, depending on the specific transmission type (Full Powershift or Semi-Powershift). This means the controller has either lost its connection to the solenoid, the solenoid's wiring has shorted out, or the voltage in the circuit is outside the expected range. The fault directly impacts the hydraulic control of the transmission's high range clutch pack, which can cause the tractor to fail to shift into or out of the high range gears.

• T7 Series
• T8 Series
• T9 Series
• T8.275
• T8.300
• T8.320
• T8.330
• T8.350
• T8.360
• T8.380
• T8.390
• T8.410
• T8.420
• T8.435

1. 1

   Visually inspect the wiring harness leading to the transmission and the high range clutch solenoid for chafing, cuts, or corrosion.

2. 2

   Disconnect and inspect the electrical connectors for the solenoid and the transmission controller for bent or corroded pins, ensuring a secure connection.

3. 3

   Perform a solenoid resistance test by measuring across the two pins of the disconnected solenoid (typical resistance is 8-11 Ohms). An infinite reading indicates an open circuit, while zero indicates an internal short.

4. 4

   Check for a short to ground by probing the wiring harness connector pins to a chassis ground.

5. 5

   Check for an open circuit in the harness by testing continuity on each wire between the solenoid connector and the transmission controller connector.

1. 1

   Safety First

   Park the tractor on a level surface, engage the park brake, and disconnect the battery.

2. 2

   Locate the Solenoid

   The clutch solenoids are generally located in the control valve assembly, which is attached to the right side of the transmission housing. Accessing this area may be labor-intensive.

3. 3

   Accessing the Transmission

   Depending on the specific tractor model, accessing the solenoid may require removing the right-hand side steps, covers, and potentially the right rear wheel. In more involved cases, it could necessitate jacking up the cab and removing the diesel tank and hydraulic pump.

4. 4

   Solenoid Replacement

   Thoroughly clean the area around the solenoid to prevent contamination of the hydraulic system. Disconnect the electrical connector. Unscrew the solenoid from the valve body. Be prepared for some hydraulic oil to leak out. Ensure the new solenoid has the correct O-rings and install them carefully. Screw the new solenoid into the valve body and torque it to the manufacturer's specification. Reconnect the electrical connector.

5. 5

   Reassembly and Testing

   Reassemble all components that were removed. Reconnect the battery. Start the tractor and check for any hydraulic leaks. Clear the fault codes using a diagnostic tool. Operate the tractor to ensure the high range engages correctly and that the fault code does not reappear. A transmission calibration may be required after replacing a transmission component.