Case IH 1762-04 - UCM – UCM: Charge pump pressure sensor voltage low

The analog voltage signal returning from the sensor to the computer is below the minimum acceptable threshold. This typically means the sensor's signal circuit is shorted to ground, the sensor is completely unplugged, the wiring harness is damaged, or the sensor has failed internally.

• MAGNUM AFS Connect
• Magnum series
• Magnum 380 RT CVX 4WD
• Puma series
• Maxxum series

1. 1

   Inspect the sealed multi-pin weather-pack connector on the sensor for mud, moisture, corrosion, or mechanical damage

2. 2

   Test the wiring harness to ensure there is no open circuit or short to ground

3. 3

   Verify that the sensor is receiving its required 5V DC (±10%) regulated reference voltage from the UCM

4. 4

   Test the actual hydraulic charge pressure using a mechanical gauge (OEM Tool #380200015) to rule out an actual failing charge pump

1. 1

   Depressurize the System

   Ensure the tractor is turned off and relieve the hydraulic/transmission system pressure before removing the sensor to prevent high-pressure fluid injection injuries.

2. 2

   Disconnect

   Unplug the electrical connector from the charge pump pressure sensor.

3. 3

   Remove the Sensor

   Unthread the faulty pressure sensor from the transmission housing or hydraulic manifold.

4. 4

   Install the New Sensor

   Thread in the direct replacement sensor. Ensure that any required O-rings are properly seated to prevent leaks.

5. 5

   Reconnect

   Plug the wiring harness back into the new sensor, ensuring the weather-pack seal clicks into place.

6. 6

   Test

   Start the tractor, check the installation site for hydraulic leaks, and use a diagnostic scan tool to clear the 1762-04 fault code.