Massey Ferguson 04.02.05 – TRANS: Transmission High Pressure Sensor 2 Signal Voltage Issue

The transmission control module has detected an abnormal or out-of-range voltage signal from Transmission High Pressure Sensor 2 (X34), which is responsible for transmitting the instantaneous hydrostatic/hydraulic oil pressure in the high-pressure system.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 7600 Series
• 8600 Series

1. 1

   Locate Transmission High Pressure Sensor 2 (X34) on the transmission housing and visually inspect the wiring harness and connector for corrosion, moisture, or damaged pins.

2. 2

   Verify that the 8.5V reference supply is present at the sensor connector when the key is ON.

3. 3

   Check for continuity and ensure there are no shorts to ground or power on the signal wire running between the sensor and the TRANS module.

4. 4

   If wiring is intact, verify the actual transmission high pressure using a mechanical gauge at the transmission's PH union to ensure the issue is strictly electrical (sensor failure) and not an actual extreme pressure anomaly.

1. 1

   Power off the tractor, engage the ParkLock/handbrake, and disconnect the battery.

   Ensure the tractor is safely secured before beginning work.

2. 2

   Clean the area around Sensor 2 (X34).

   This prevents debris from entering the transmission during sensor removal.

3. 3

   Disconnect the electrical connector and unthread the faulty high-pressure sensor.

   Be prepared for minor oil loss and ensure the system is depressurized before removal.

4. 4

   Install the new high-pressure sensor.

   Torque the new sensor to OEM specifications.

5. 5

   Reconnect the wiring harness and the battery.

   Ensure all connections are secure.

6. 6

   Perform a transmission calibration.

   This is a crucial step that must be carried out systematically after changing the sensor. Execute the procedure via the tractor terminal with the hand brake applied (or ParkLock engaged), Power Control lever in neutral, and Hare/Tortoise range in neutral.

7. 7

   Clear the fault codes and test drive the tractor.

   Verify that the repair was successful and the code does not return.