Case IH 5062 – UCM (Universal Control Module): Port Lock Valve (On/Off) Solenoid Supply Shorted To Ground

The control module has sent a signal to energize the Loader Port Lock solenoid, but no voltage is detected on the circuit. This indicates that the power supply wire to the solenoid, or the solenoid coil itself, is shorted directly to the machine's chassis ground. When this code is active, the machine's loader hydraulics are completely disabled for safety.

• skid steer
• SR130
• SR150
• SR175
• SV185
• SR200
• SR220
• SR250
• SV250
• SV300
• TR270
• TR320
• TV380
• L218
• L220
• L315
• L334

1. 1

   Inspect the wiring harness leading to the Port Lock Valve solenoid on the main loader control valve for chafed insulation, pinched wires, or exposed copper touching the metal frame.

2. 2

   Disconnect connector X-412 (Loader Lock Port Lock Valve Connection to Chassis) and inspect the pins for corrosion, moisture, or melting.

3. 3

   With the connector unplugged, use a multimeter to measure the resistance across the solenoid coil pins, and from the power pin to the solenoid casing. Continuity to the casing indicates an internally shorted solenoid.

4. 4

   Disconnect the harness at the UCM and at the solenoid (X-412). Test the supply wire for continuity to the chassis ground to check for a shorted wiring harness.

1. 1

   Relieve Hydraulic Pressure

   Lower the loader arms to the ground. Turn off the engine. Turn the ignition back on (without starting the engine) and move the joysticks in all directions to relieve residual hydraulic pressure.

2. 2

   Access the Valve

   Open the cab or access panels to reach the main loader hydraulic control valve where the Port Lock Valve solenoid is mounted.

3. 3

   Disconnect Electrical Supply

   Unplug the X-412 electrical connector from the Port Lock Valve solenoid.

4. 4

   Repair the Short

   If the harness is damaged: Trace the wire back toward the UCM. Cut out the chafed/shorted section of the wire and repair it using weather-sealed heat-shrink butt connectors, or replace that section of the wiring harness. If the solenoid is internally shorted: Remove the retaining nut holding the solenoid coil to the valve stem. Slide the old coil off. Slide the new OEM solenoid coil onto the stem and torque the retaining nut to factory specifications.

5. 5

   Reassembly and Testing

   Reconnect the X-412 connector. Turn the ignition on and use the Electronic Service Tool (EST) or the instrument cluster display to verify the fault code has changed from "Active" to "Inactive". Clear the code and test the loader hydraulic functions.