Case IH 2737 (517974.06) - DEC – DEC: F2 solenoid - LSD short to HSD

This code indicates an electrical short circuit in the F2 synchronizer/clutch solenoid circuit. Specifically, the Low Side Driver (LSD) circuit is shorted to the High Side Driver (HSD) circuit. This means the ground-side control wire is making direct electrical contact with the power-side control wire, bypassing the solenoid coil's resistance. This is typically caused by a chafed wiring harness, a melted connector, or an internal short within the F2 solenoid coil itself.

• VESTRUM CVX
• Magnum Series
• Puma Series
• Maxxum Series

1. 1

   Visually inspect the transmission wiring harness routing from the DEC to the transmission valve block for pinched wires, rubbed insulation, or debris that could cause the LSD and HSD wires to short together.

2. 2

   Disconnect the electrical connector at the F2 solenoid and measure the resistance across the two terminals. A healthy solenoid reads between 8 to 11 Ohms. A significantly lower reading or 0 Ohms indicates an internal short.

3. 3

   If resistance is within spec, temporarily swap the F2 solenoid with an adjacent, identical solenoid (such as F1 or R1). Clear codes and operate the tractor. If the fault code changes to the new location, the solenoid is defective. If it remains 2737, the short is in the wiring harness or the DEC.

1. 1

   Park and disconnect battery

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and disconnect the battery to prevent electrical spikes.

2. 2

   Clean valve block area

   Clean the area around the transmission control valve block thoroughly to prevent dirt from entering the hydraulic system.

3. 3

   Locate F2 solenoid

   Locate the F2 solenoid on the valve block (refer to the specific model's service manual for the exact port location, as it varies between Powershift and CVT models).

4. 4

   Disconnect electrical connector

   Depress the locking tab and disconnect the 2-pin electrical connector from the F2 solenoid.

5. 5

   Remove retaining hardware

   Remove the retaining bolts or snap ring securing the solenoid to the valve block.

6. 6

   Remove faulty solenoid

   Carefully pull the faulty F2 solenoid straight out of the bore. Have a rag ready to catch a small amount of residual transmission fluid.

7. 7

   Lubricate new solenoid

   Lubricate the O-rings on the new solenoid with clean Case IH Akcela transmission fluid.

8. 8

   Install new solenoid

   Insert the new solenoid into the valve block, ensuring it seats fully.

9. 9

   Secure solenoid

   Reinstall and tighten the retaining bolts to the OEM torque specification.

10. 10

    Reconnect electrical connector

    Reconnect the electrical connector, ensuring the weather seal is intact and the lock clicks into place.

11. 11

    Clear fault codes

    Reconnect the battery, turn the key on, and use the tractor's diagnostic display to clear the fault codes.

12. 12

    Perform calibration

    Depending on the tractor model, a transmission clutch/synchronizer calibration may need to be performed via the cab display after replacing a transmission solenoid.