Massey Ferguson 04.2.90 – Transmission Controller (TRANS or TRANS1): Issue With Speed Sensor Values

The controller is receiving erratic, out-of-range, or missing signals from the transmission speed sensor, which monitors the rotational speed of the transmission components.

• 4707
• 4708
• 4709
• 4710
• T4 (2015-2021)
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• T4 Emissions Models (2017-2023)

1. 1

   Perform software diagnostics using Massey Ferguson's Wintest software to monitor live data and identify the exact failure point

2. 2

   Check the sensor's electrical resistance (should measure approximately 450 Ohms +/- 20 when the tractor is stopped)

3. 3

   Inspect the sensor wiring harness, pins, and earth (ground) connections for corrosion, breaks, or shorts

4. 4

   Verify the sensor air gap is correct above the differential ring gear, as an incorrect gap causes erratic values

1. 1

   Adjust the Sensor Air Gap

   Loosen the counter-nut on the sensor. Apply a small amount of thread sealant (e.g., Loctite 5922) to the threads. Carefully screw the sensor in fully until it bottoms out against the gear. Unscrew the sensor by exactly ¾ of a turn to set the correct air gap. Tighten the counter-nut to approximately 6 Nm.

2. 2

   Replace the Sensor

   If adjusting the air gap or repairing the wiring does not resolve the issue, remove the old sensor and install a new OEM transmission speed sensor following the same air gap adjustment procedure above.

3. 3

   Clear Codes

   Use the diagnostic tool to reset the system and clear the DTC. Test drive the tractor to ensure the transmission shifts correctly and the code does not return.