Massey Ferguson 04.X.86 – Transmission Control Module (TCU) / Autotronic 4: Transmission High Pressure Sensor Signal Voltage Issue (TRANS)

The electronic system is receiving an electrical signal voltage from the transmission high-pressure sensor that is out of the expected range (likely due to a short, open circuit, or failed sensor).

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 8690

1. 1

   Locate the transmission high-pressure sensor (designated as X34 / X9 on ML260 transmission diagrams)

2. 2

   Inspect the sensor's electrical connector and wiring harness routing back to the Autotronic 4 / TRANS module for signs of chafing, corrosion, or disconnected pins

3. 3

   Test the sensor's signal voltage with a multimeter to determine if there is a short to ground, a short to power, or an open circuit

1. 1

   Relieve hydraulic pressure

   Safely relieve any residual hydraulic pressure in the transmission system.

2. 2

   Replace sensor

   Remove and replace the faulty Transmission High Pressure Sensor.

3. 3

   Perform calibration

   Mandatory Calibration: A transmission calibration procedure must be carried out systematically after changing the transmission high pressure sensor.

4. 4

   Set calibration preliminary conditions

   Calibration Preliminary Conditions (must be performed immediately after the range calibration): Hand brake applied or ParkLock engaged. Power Control lever in the neutral position. High/low speed range (Hare/Tortoise) in neutral (the Hare/Tortoise symbols will flash alternately on the right-hand screen).

5. 5

   Execute calibration

   Execute the transmission calibration via the tractor terminal/diagnostic tool to validate the new sensor.

6. 6

   Clear DTCs

   Clear the DTC codes from the system.