Case IH 51075 – AUX (Auxiliary Valve Controller) / TMF (Tractor Multi-Function): Aux 3rd Lower solenoid failed open or short circuit

This indicates an electrical failure in the circuit controlling the lowering function of the 3rd auxiliary remote hydraulic valve. The system has detected that the circuit is either broken (an open circuit, such as a severed wire or a burnt-out solenoid coil) or shorted to ground (a bare wire touching the chassis or an internal short in the coil).

• MX Magnum
• Case IH MX Magnum Series (MX180, MX200, MX210, MX220, MX230, MX240, MX255, MX270, MX285)
• Case IH TG Series
• Case IH Steiger Series

1. 1

   Visually inspect the 3rd remote hydraulic valve block at the rear of the tractor, checking the wiring harness and connector to the 'Lower' solenoid for chafing, broken wires, or severe corrosion.

2. 2

   Perform a coil resistance test by disconnecting the electrical connector from the 3rd remote lower solenoid and measuring resistance across the pins (infinity/OL confirms an open coil, 0 ohms confirms a dead short).

3. 3

   If the solenoid tests normal, perform a harness continuity test from the solenoid connector back to the AUX/TMF controller to check for breaks or shorts to the tractor frame.

1. 1

   Turn off the tractor, relieve all hydraulic system pressure, and disconnect the battery to prevent electrical spikes.

   Turn off the tractor, relieve all hydraulic system pressure, and disconnect the battery to prevent electrical spikes.

2. 2

   Locate the 3rd remote hydraulic valve assembly at the rear of the machine.

   Locate the 3rd remote hydraulic valve assembly at the rear of the machine.

3. 3

   Disconnect the electrical harness from the lower solenoid of the 3rd remote valve.

   Disconnect the electrical harness from the lower solenoid of the 3rd remote valve.

4. 4

   If the diagnostic checks proved the solenoid coil is faulty, remove the retaining nut or fastener holding the solenoid coil to the valve cartridge.

   If the diagnostic checks proved the solenoid coil is faulty, remove the retaining nut or fastener holding the solenoid coil to the valve cartridge.

5. 5

   Slide the old solenoid coil off the valve stem.

   Slide the old solenoid coil off the valve stem. (Note: If the entire cartridge valve is faulty, unscrew the cartridge from the valve body, being prepared to catch a small amount of hydraulic fluid).

6. 6

   Install the new solenoid coil (or cartridge assembly) and tighten it to the manufacturer's torque specification.

   Install the new solenoid coil (or cartridge assembly) and tighten it to the manufacturer's torque specification.

7. 7

   Reconnect the electrical harness, ensuring the connector is fully seated, clean, and locked.

   Reconnect the electrical harness, ensuring the connector is fully seated, clean, and locked.

8. 8

   Reconnect the battery, start the tractor, and test the 3rd remote valve's lowering operation. Clear the fault codes from the instrument cluster/display.

   Reconnect the battery, start the tractor, and test the 3rd remote valve's lowering operation. Clear the fault codes from the instrument cluster/display.