Massey Ferguson 04.00.40 – TRANS1: Issue With Speed Sensor Values (TRANS1)

The transmission control system is receiving erratic, implausible, or missing signal values from the transmission speed sensor.

• 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
• 6600 Series
• 6700S Series
• 7600 Series

1. 1

   Perform diagnostic tests on the sensors using Wintest software to monitor active and requested speed values to confirm if the sensor is truly failing (Note: replacing sensors without performing Wintest diagnostics may void warranty claims).

2. 2

   Inspect the wiring harness and the electrical connector at the sensor for corrosion, moisture, or physical damage, which can cause signal loss mimicking a failed sensor.

1. 1

   Locate the Sensor

   The transmission/ground speed sensor is typically threaded into the transmission housing, input shaft area, or the hydraulic pump underneath the tractor, depending on the specific model and transmission type (e.g., Dyna-4, Dyna-6, or Dyna-VT).

2. 2

   Preparation

   Park the tractor on flat ground and clean the area around the sensor thoroughly to prevent dirt or debris from entering the transmission housing. Have a catch pan ready, as a small amount of transmission fluid may leak when the sensor is removed.

3. 3

   Removal

   Disconnect the electrical wiring harness connector from the sensor. Unscrew the faulty speed sensor from the housing.

4. 4

   Installation

   Thread the new OEM speed sensor into the housing and tighten it to the manufacturer's torque specification.

5. 5

   Reconnection

   Reconnect the electrical harness, ensuring the connector clicks securely into place.

6. 6

   Calibration/Clearing

   Clear the 04.00.40 fault code using the Wintest software or the tractor's Dash Control Center. Perform a test drive to verify that the transmission shifts correctly and the speed values are accurately reported.