Case IH 519075-05 - UCM – UCM: Rear hitch top link extend solenoid current low.

The control module has detected that the electrical current flowing to the rear hitch top link extend solenoid is lower than the expected operating range. This typically means there is an open circuit, a broken wire, a disconnected plug, or a failed (open) solenoid coil preventing current flow.

• MAGNUM AFS Connect
• Case IH Puma Series (165, 180, 195, 210, 225 CVX)
• Case IH Maxxum Series (Tier 3 and newer)
• Case IH Farmall Series (95U, 105U, 115U Pro)

1. 1

   Identify wire 4055 (White), which is the feed for the top link extend solenoid.

2. 2

   Inspect the electrical connector at the top link extend solenoid on the rear hitch hydraulic valve block for disconnected plugs, pushed-out pins, or severe corrosion.

3. 3

   Disconnect the harness from the UCM and the solenoid, and test wire 4055 (White) for continuity to ensure the wire is not broken or rubbed through.

4. 4

   Verify that the ground circuit for the solenoid valve block is intact and free of excessive resistance.

5. 5

   Use a multimeter to measure the resistance across the pins of the top link extend solenoid. An infinite or out-of-spec high resistance reading confirms the internal coil is open and has failed.

1. 1

   Preparation

   Park the tractor on a level surface, lower the rear hitch completely to relieve mechanical tension, turn off the engine, and remove the key.

2. 2

   Relieve Pressure

   Actuate the hydraulic remotes/hitch controls with the key on (engine off) to relieve any residual hydraulic pressure in the system.

3. 3

   Access the Valve Block

   Locate the rear hitch EHR valve block at the rear of the tractor and identify the top link extend solenoid (trace wire 4055).

4. 4

   Wiring Repair

   If the diagnostic checks revealed a break in wire 4055, splice and repair the wire using OEM-approved weather-sealed connectors.

5. 5

   Solenoid Replacement

   If the coil is open, disconnect the electrical connector from the faulty solenoid. Remove the retaining nut or snap ring holding the solenoid coil to the hydraulic valve cartridge. Slide the old solenoid coil off the valve stem, slide the new solenoid coil onto the stem, and secure it with the retaining nut/clip.

6. 6

   Reassembly & Testing

   Reconnect the electrical harness. Turn the key on, clear the stored 519075-05 fault code from the UCM, and test the rear hitch top link extend function to verify the repair.