New Holland UCM 5063 – UCM (Universal Control Module): Loader Port Lock: Solenoid Supply Short to Power

This code indicates that the control module has detected a higher-than-normal voltage (a short circuit to the power supply) on the circuit responsible for the Loader Port Lock Solenoid. The port lock solenoid is a safety device that, when de-energized, prevents hydraulic oil flow to the boom and bucket cylinders.

• L218
• L220
• L223
• L225
• L230
• L315
• L334
• SR130
• SR160
• SR175
• SR220
• SR250
• SV185
• SV250
• SV300
• TR320
• TV380

1. 1

   Connect the Electronic Service Tool (EST) to the service port, start and operate the machine to verify if the fault code is currently active.

2. 2

   Inspect the UCM and the Loader Port Lock solenoid connections (specifically connector X-412) to ensure they are secure, tight, and free of corrosion, abrasion, or damage.

3. 3

   Trace and inspect the wiring harness from the UCM to the Loader Port Lock solenoid to ensure there is no chafing, melting, or incorrect attachment causing a short to a power source.

4. 4

   Disconnect the solenoid and measure the resistance across the Loader Port Lock solenoid terminals (Pin 1 and Pin 2). The resistance should be greater than 5 Ω.

1. 1

   Harness/Connector Repair

   If the visual inspection reveals damage to the wiring harness or connectors, repair or replace the affected harness section. Clear the codes and retest.

2. 2

   Solenoid Replacement

   If the resistance measured across the solenoid terminals is less than 5 Ω, the solenoid has an internal short circuit. Remove and replace the Loader Port Lock Solenoid.

3. 3

   UCM Testing

   If the harness is in good condition and the solenoid resistance is greater than 5 Ω, the UCM likely has an internal failure. Temporarily install a known-good UCM, calibrate it, and retest the machine to confirm the fault is eliminated before permanently replacing the module.