Massey Ferguson T4192 – Transmission Control Module (TRANS): Issue With Signal Voltage From Left Brake Pedal Sensor DYNA VT (TRANS)

The transmission controller is receiving an erratic, out-of-range, or completely interrupted electrical signal from the left brake pedal position sensor (designated as component X66 in the wiring schematics).

• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 7615
• 7620
• 7616
• 7618
• 7619
• 7626
• 7624
• 6614
• 6615
• 6616
• 8670
• 8690

1. 1

   Visually inspect the left brake pedal sensor (X66) and its mounting bracket for physical damage.

2. 2

   Inspect the pigtail and main harness connector to the X66 sensor for pushed pins, corrosion, or wire chafing.

3. 3

   Back-probe the sensor connector to verify it receives the correct reference voltage and ground from the transmission controller. Monitor the signal wire voltage while slowly depressing the pedal; it should sweep smoothly without dropping out.

4. 4

   Check the CAN communication lines between the pedal sensors and the transmission controller to ensure they are intact.

1. 1

   Power Down

   Turn off the tractor and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Access the Sensor

   Remove any lower dash or steering column trim panels required to access the brake pedal pivot assembly.

3. 3

   Disconnect

   Unplug the electrical connector from the left brake pedal sensor (X66).

4. 4

   Remove

   Unbolt the sensor from its mounting bracket on the pedal assembly. Note the orientation of the sensor arm/actuator.

5. 5

   Install

   Mount the new OEM sensor in the exact same orientation. Torque the mounting hardware to standard spec (do not overtighten plastic housings).

6. 6

   Reconnect

   Plug in the electrical connector, ensuring the locking tab clicks into place.

7. 7

   Reassemble & Clear

   Reconnect the battery, turn the key to the ON position, and use a diagnostic scan tool to clear the T4192 fault code.

8. 8

   Test

   Depress the left brake pedal several times to ensure the code does not return and that the transmission responds correctly to braking inputs.