Massey Ferguson 4.03.91 – TRANS1: Issue With Speed Sensor Values (TRANS1)

The transmission control system is receiving irregular, missing, or out-of-range signals from the intermediate transmission speed sensor (TR25).

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5713SL T4
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 3000 Series
• 3100 Series
• 3600 Series
• 5400 Series
• 6100 Series
• 6200 Series
• 6400 Series
• 6600 Series
• 7600 Series
• 8100/8200 Series

1. 1

   Use Wintest software diagnostics to read the active/requested values and verify the sensor's output

2. 2

   Verify the wiring harness and connections (2-pin connector: Pin 1 Signal, Pin 2 Ground) before assuming the sensor is faulty

3. 3

   Perform a resistance test with the tractor stopped; a healthy induction sensor should read 450 Ohms +/- 20 Ohms

4. 4

   Perform a voltage test to check for an alternating voltage signal when the pinion gear is rotating

1. 1

   Locate the Sensor

   The intermediate speed sensor (TR25) is located close to the gearbox cover.

2. 2

   Remove the Old Sensor

   Disconnect the wiring harness and unscrew the faulty sensor.

3. 3

   Prepare the New Sensor

   Apply a small amount of Loctite 5922 to the threads of the new sensor.

4. 4

   Set the Air-Gap

   Screw the new sensor all the way in until it bottoms out (in abutment) on the pinion gear. Unscrew the sensor by exactly 3/4 of a turn to set the correct air-gap.

5. 5

   Secure the Sensor

   Tighten the locknut to approximately 6 Nm.

6. 6

   Clear Codes

   Reconnect the wiring harness and clear the fault codes from the tractor's computer to ensure the TRANS1 module recognizes the new sensor.