New Holland TMF 87 – TMF (Tractor Multi-Function) Controller / Instrumentation Controller: Ground Speed Signal is failed in the Instrumentation Controller.

The Instrumentation Controller is no longer receiving a valid, stable, or in-range signal from the machine's ground speed sensor (which can be a transmission-mounted speed sensor or a radar-based true ground speed sensor). Without this signal, the tractor cannot accurately calculate wheel slip, manage automatic transmission shifting, or display speed on the dash.

• TG Series
• TG210
• TG230
• TG255
• TG285
• T8 Series
• T8000 Series
• TL-A Series
• CX Series
• CX6.80
• CX6.90
• CX7.90
• CX8080
• CX8090
• Magnum Series
• Steiger Series
• MX/TG Series

1. 1

   Monitor live data for INST GROUND SPEED - WHEEL or INST TRANS OUTPUT SPEED while driving to see if the value remains at zero or fluctuates erratically.

2. 2

   Inspect the wiring harness and connectors between the ground speed sensor and the Instrumentation Controller for rubbed wires, corrosion, or an open/short circuit to ground.

3. 3

   Perform a sensor swap test on older models by temporarily swapping the transmission ground speed sensor with the engine speed sensor to see if the fault follows the sensor.

1. 1

   Locate the Sensor

   Locate the ground speed sensor. Depending on your specific machine configuration, it will either be a magnetic pickup sensor located on the right side of the center housing/rear of the transmission, or a radar sensor mounted under the cab.

2. 2

   Disconnect Power

   Turn off the machine and disconnect the battery ground to protect the instrumentation circuits.

3. 3

   Remove the Sensor

   Disconnect the electrical connector from the sensor. Remove the retaining bolt(s) (typically an M6 hex bolt) securing the sensor or its mounting bracket to the housing.

4. 4

   Extract and Inspect

   Pull the old sensor out of the transmission housing. Inspect the port for any metal debris, which could indicate internal transmission wear interfering with the magnetic pickup.

5. 5

   Install the New Sensor

   Apply a light coat of clean oil or grease to the O-ring of the new sensor. Push it into the housing and secure it with the retaining bolt.

6. 6

   Reconnect and Calibrate

   Reconnect the electrical harness. Reconnect the battery.

7. 7

   Clear Codes and Test

   Clear the TMF 87 fault code using the tractor's diagnostic menu. Test drive the machine while monitoring the ground speed on the dash to verify the repair.