Massey Ferguson 04.01.B8 – TRANS1: Issue With Intermediate Speed Sensor Values (TRANS1)

The transmission controller detects an illogical or missing signal from the intermediate speed sensor. This typically occurs when no intermediate speed is detected while the current forward speed is greater than 0 km/h, or a discrepancy is detected between the engine speed and intermediate speed (e.g., a calculated slip greater than 10% for more than 700 milliseconds).

• 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
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613

1. 1

   Perform a visual and wiring inspection of the sensor contacts, harness connections, and wiring for damage, backed-out pins, or corrosion.

2. 2

   Perform a resistance test with the ignition off: disconnect the sensor and measure resistance across the two pins at room temperature (should read 450 Ohms +/- 20 Ohms).

3. 3

   Perform a voltage test to check for alternating voltage (AC) output from the sensor while the internal gear/ring gear is rotating.

4. 4

   Perform a software check using Massey Ferguson Wintest diagnostic software to monitor active intermediate speed sensor values in real-time for signal dropouts under load.

1. 1

   Locate the Sensor

   The intermediate speed sensor is an inductive sensor typically located on the transmission housing (often above the differential ring gear, depending on the exact model).

2. 2

   Removal

   Disconnect the electrical harness, loosen the counter-nut, and unscrew the faulty sensor from the housing.

3. 3

   Preparation

   Apply a small amount of thread sealant (Loctite 5922 is recommended by OEM manuals) to the threads of the new sensor.

4. 4

   Air Gap Adjustment

   Manually screw the new sensor in fully until it bottoms out against the internal gear. Carefully unscrew the sensor by exactly 3/4 of a turn to set the correct air gap.

5. 5

   Secure

   Tighten the counter-nut to approximately 6 Nm to lock the sensor in place.

6. 6

   System Reset

   Reconnect the harness. To reset the system logic, move the PowerControl lever to the neutral position, then press and release the clutch pedal. Clear the inactive 04.01.B8 code via the diagnostic interface.