New Holland UCM 9156 – UCM: Hydraulics Enable: Button Error from AIC

The Universal Control Module (UCM) is receiving an implausible, erroneous, or continuous signal from the 'Hydraulics Enable' (Operate) button on the Advanced Instrument Cluster (AIC).

• L213
• L215
• L216
• L218
• L220
• L221
• L223
• L225
• L228
• L230
• C227
• C232
• C238
• SR130
• SR150
• SR175
• SV185
• TR270

1. 1

   Check for operator error: look for a 'CRKOn' message indicating the button is being pressed while attempting to start the machine.

2. 2

   In extremely cold temperatures, warm the machine to operating temperature and cycle the hydraulics off and back on.

3. 3

   Inspect the Hydraulics Enable button on the right-hand cab post (AIC panel) for physical sticking, debris, or damage.

4. 4

   Inspect the wiring harness connecting the Advanced Instrument Cluster to the UCM for pinched wires, shorts, or open circuits.

5. 5

   Verify that the UCM ground wire is secure and free of corrosion.

1. 1

   Safely Park the Machine

   Lower the boom (if possible), turn off the engine, engage the parking brake, and disconnect the battery to prevent electrical shorts during repair.

2. 2

   Clean the AIC Panel

   If the Hydraulics Enable button is simply sticking due to dirt or debris, carefully clean the perimeter of the button on the Advanced Instrument Cluster using an electronics-safe cleaner.

3. 3

   Test the Harness

   Using a multimeter, test the continuity of the wiring harness between the AIC and the UCM. Repair or replace any damaged wire segments or corroded connector pins.

4. 4

   Replace the AIC

   The Hydraulics Enable button is integrated directly into the Advanced Instrument Cluster. If the button has failed internally (shorted or open circuit inside the panel) and cannot be freed, the entire Instrument Cluster must be replaced.

5. 5

   Install the New Cluster

   Mount the new AIC to the right-hand cab post and plug in the main harness connector.

6. 6

   Relearn/Clear Codes

   Reconnect the battery. Turn the ignition on. Use the New Holland Electronic Service Tool (EST) to clear the UCM 9156 fault code and verify that the UCM recognizes the new cluster configuration.

7. 7

   Operational Test

   Start the machine (without pressing the button). Once running, press and release the Hydraulics Enable button within 10 seconds. Verify that the park brake disengages and the loader/drive hydraulics become active.