New Holland UCM 9160 – UCM (Universal Control Module): Pattern Select (ISO/H): Short to Power

The control module has detected a short circuit to a power source (voltage too high) in the circuit for the ISO/H Pattern Select switch. This switch allows the operator to toggle the joystick control patterns between ISO and H configurations.

• 200 Series
• 300 Series
• L213
• L218
• L220
• L223
• L230
• C227
• C232
• C238
• C337
• C345
• SR130
• SR150
• SR175
• TR270
• TV380

1. 1

   Inspect the Switch: Check the ISO/H pattern select rocker switch on the cab control panel for physical damage, sticking, or internal shorting.

2. 2

   Harness Inspection: Trace the wiring harness from the back of the pattern select switch to the UCM. Look for chafed wires, melted insulation, or pinched areas where the switch signal wire might be touching a 12V power source.

3. 3

   Multimeter Testing: Disconnect the switch and turn the key ON. Use a multimeter to check the harness-side pins for unexpected voltage. If voltage is present on the signal return wire while disconnected, the harness is shorted. If the harness tests fine, the switch is likely shorted internally.

4. 4

   UCM Connections: Inspect the UCM connectors for moisture, corrosion, or bent pins that could be bridging a power pin to the pattern select circuit.

1. 1

   Power Down

   Turn off the machine, lower the loader arms to the ground, and disconnect the battery.

2. 2

   Access the Switch

   Remove the retaining screws for the cab control panel/pillar where the ISO/H switch is mounted.

3. 3

   Repair the Short

   If the wiring harness was found to be damaged during diagnostics, repair the shorted wires using heat-shrink butt connectors or replace the affected harness section. If the switch failed the continuity test, remove the old switch from the panel and snap the replacement switch into place.

4. 4

   Reassemble

   Reconnect the wiring harness to the switch and reinstall the cab control panel.

5. 5

   Clear Codes & Calibrate

   Reconnect the battery and turn the key ON. Clear the inactive fault codes from the display.

6. 6

   Test Operation

   Ensure the joysticks are in the neutral position (the switch will not change patterns if the joysticks are engaged). Press and hold the ISO/H pattern select switch for a few seconds. An audible alarm should sound, and the switch should illuminate on the selected side to confirm the pattern change was successful. Verify that code 9160 does not return.