Case IH 51055 – AUX Controller: Aux 1st Lower solenoid failed open or a short circuit to ground

The controller has detected an electrical fault—either a broken connection (open circuit) or a short to ground—on the circuit that controls the lower solenoid of the first auxiliary remote hydraulic valve.

• MX Magnum
• STX Steiger
• Case IH MX Magnum Series
• Case IH TG Series
• Case IH Steiger / STX Series
• Quadtrac

1. 1

   Inspect the valve connector (e.g., C340) at the 1st remote valve for damage, corrosion, bent pins, or dislocated pins

2. 2

   Test the resistance of the valve solenoid directly at the valve connector using a multimeter (an infinite reading indicates a failed open coil)

3. 3

   Test the wiring harness from the AUX controller (e.g., connector C054) to the remote valve to verify there is no continuity from any pins to a clean ground or power when the lever is in Neutral

4. 4

   Ensure the AUX controller has a good connection to the battery and is properly grounded to rule out a hardware or software glitch

1. 1

   Disconnect Power

   Shut down the tractor and disconnect the power supply to the solenoid.

2. 2

   Locate the Solenoid

   Go to the remote hydraulic valve stack at the rear of the tractor. Each remote valve has two solenoids (one on top for raise, one on the bottom for lower). Locate the bottom solenoid on the #1 remote valve.

3. 3

   Inspect and Clean

   Disconnect the wiring harness and inspect for loose or damaged wires. Repair or replace the harness if chafing or wire breaks are found.

4. 4

   Replace the Solenoid

   If the wiring is intact but the solenoid coil failed the resistance test or shows physical signs of damage/corrosion, remove the retaining hardware and slide the old solenoid off the valve cartridge.

5. 5

   Install and Test

   Install the new solenoid, reconnect the wiring harness, clear the fault codes, and restart the tractor to test the 1st remote lower function.