Case IH 2563 (519167.01) - DEC – UCM: HST Inlet (Hydro Gport) - Pressure Too Low

This indicates that the hydrostatic transmission (HST) inlet charge pressure at the G-port has dropped below the acceptable operating threshold.

• VESTRUM CVX
• Case IH Puma CVT / AutoCommand series (e.g., Puma 115 through Puma 240 CVT)

1. 1

   Verify that the tractor battery power supply has not been connected to an external power supply (like a jump box or charger while running)

2. 2

   Check the hydro Gport pressure sensor connector (X-916) and the UCM connector (X-955) for secure connection, damage, correct pin position, and tight fit

3. 3

   Disconnect connector X-916 and measure the voltage to ensure the sensor is receiving a +5 Volt reference signal from the UCM

1. 1

   Disconnect external power supply

   If an external power supply was causing the voltage/pressure reading anomaly, simply disconnecting it resolves the issue.

2. 2

   Repair wiring or replace connector

   If a fault is indicated during the wiring and connector inspection (e.g., damaged pins, loose fit, or lack of 5V reference), repair the wiring harness or replace the connector as required.

3. 3

   Replace hydro Gport pressure sensor

   If the connectors are okay and the 5V reference is present, the primary failure mode is a faulty hydro Gport pressure sensor (charge pressure sensor hydrostat). Remove and replace the sensor.

4. 4

   Clear error code and test

   Once the cause of the error code has been rectified, clear the error code from the UCM and test the hydrostatic system for normal operation.