Massey Ferguson 04.02.40 – Transmission Control Module (TRANS1): Issue With Speed Sensor Values (TRANS1)

The tractor's computer is receiving erratic, out-of-range, or missing rotational speed data from the transmission speed sensor. Operators may experience rough shifting, poor fuel economy, or a failure to engage gears properly.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613

1. 1

   Wiring and Connections: Verify that the sensor is actually faulty. Inspect the wiring harness and the electrical connector at the transmission speed sensor for open circuits, corrosion, or loose pins.

2. 2

   Physical Inspection: Check the sensor body for physical damage, heavy dirt, oil mist, or moisture ingress, as these sensors endure extreme conditions near the transmission components.

3. 3

   Resistance Testing: If you have a multimeter, check the sensor's resistance. A healthy transmission speed sensor on many of these models should read approximately 540 Ohms (+/-).

1. 1

   Preparation

   Park the tractor on flat, level ground and turn off the engine.

2. 2

   Removal

   Locate the transmission speed sensor on the transmission housing. Disconnect the electrical wiring harness from the sensor. Unthread and remove the faulty speed sensor from the transmission block.

3. 3

   Installation

   Install the new transmission speed sensor, ensuring the O-ring or seal is properly seated to prevent transmission fluid leaks. Reconnect the electrical harness.

4. 4

   Clear Codes

   Use a diagnostic tool/software to clear the 04.02.40 fault code from the TRANS1 module.

5. 5

   Calibration

   A transmission/clutch calibration is highly recommended (and often required) after replacing driveline sensors to ensure the computer recognizes the new sensor. For Dyna-4/Dyna-6 transmissions, this typically involves warming the transmission oil to between 35°C (95°F) and 45°C (113°F) and initiating the calibration sequence via the dash and PowerShuttle lever.