Case IH 56033 – Transmission Controller (TRANS): 1F Valve Coil circuit is open or shorted to ground when valve is ON.

The transmission controller has turned on the 1F clutch solenoid coil, but the voltage on the low side of the coil is lower than expected (or the current draw is below the required limit).

• STX Steiger
• Case IH Steiger / STX Series Tractors
• Case IH Puma Series
• Case IH MX Magnum Series
• Case IH Maxxum Series

1. 1

   Coil Resistance Test: Disconnect the 1F clutch solenoid connector (C029). Measure resistance between cavity A and B. Expected: 9.4-11.4 ohms at 4°C (40°F), 9.9-12.1 ohms at 15°C (60°F), 10.3-12.7 ohms at 27°C (80°F), 11.2-13.8 ohms at 49°C (120°F). If out of spec or infinite, the coil has failed.

2. 2

   Wiring Harness Inspection: Visually inspect the wiring harness running from the 1F clutch solenoid to the transmission controller (typically under the fuse/relay panel in the cab) for chafing, pinched wires, or disconnected pins.

3. 3

   Power Supply Check: Verify that power is being supplied from the neutral latch relay to the solenoid power wire.

1. 1

   Safety First

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

2. 2

   Locate the Solenoid

   Locate the transmission valve block and identify the 1F clutch solenoid.

3. 3

   Disconnect and Remove

   Disconnect the electrical harness from the solenoid. If the diagnostic checks pointed to a failed coil, unbolt/unscrew the solenoid valve from the transmission manifold. (Be prepared for minor hydraulic fluid loss; have a catch pan ready).

4. 4

   Install New Part

   Install the replacement solenoid valve or coil. Torque to OEM specifications and reconnect the electrical harness.

5. 5

   Repair Wiring (If Applicable)

   If the solenoid tested fine but the wiring was damaged, splice and heat-shrink the broken wire, or replace the affected harness section between the transmission and the cab controller.

6. 6

   Clear Codes and Calibrate

   Reconnect the battery and turn the key on. Use the tractor's display or an Electronic Service Tool to clear the TRANS 56033 fault code.

7. 7

   Transmission Calibration

   Because a transmission clutch component was replaced or disconnected, you must perform a transmission calibration procedure (often accessed via the "Trans Setup" menu on the display) to ensure the controller learns the correct fill times and engagement pressures for the 1F clutch.