New Holland TMF 28 – Armrest Controller (ARM): Hitch Travel potentiometer is failed in the Armrest Controller

The electronic control unit is receiving an out-of-range, erratic, or missing electrical signal from the potentiometer (dial/slider) used by the operator to set the travel limits of the rear 3-point hitch.

• T6
• T7
• T8
• T9
• TS
• TS-A
• T6000 series
• T6020-T6090
• TG series
• TG255
• TJ series
• Magnum
• Puma
• MX/TG series

1. 1

   Verify the tractor's hitch configuration procedure to ensure the potentiometer was not connected incorrectly during a previous calibration.

2. 2

   Use a multimeter to test the potentiometer resistance across pins A to C (OEM spec is typically 1,000, 2,500, or 10,000 ohms ± 10% depending on the model).

3. 3

   Inspect the wiring harness between the potentiometer and the Armrest Controller for shorts or open circuits.

4. 4

   On older models (e.g., TG series), check the active terminators on the CAN bus for broken solder joints where the pins meet the board.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent short circuits while working on the sensitive armrest electronics.

2. 2

   Access the Armrest

   Remove the screws securing the right-hand armrest console cover to expose the internal electronic control boards and switches.

3. 3

   Remove the Faulty Sensor

   Locate the hitch travel potentiometer. Unplug its electrical connector and remove the retaining nut (often a 3/8-32 or 1/4-inch nut) securing it to the console housing.

4. 4

   Install the New Part

   Insert the replacement potentiometer, secure the retaining nut, and plug in the electrical connector.

5. 5

   Reassemble

   Carefully reinstall the armrest cover, ensuring no wires are pinched.

6. 6

   Recalibrate

   Reconnect the battery, power on the tractor, and navigate to the hitch configuration/calibration menu on the instrument cluster or IntelliView monitor. You must perform the hitch calibration procedure so the Armrest Controller can learn the minimum and maximum voltage sweeps of the new potentiometer.