New Holland ARMRE 79 – Armrest Controller (ARM / ARU): HITCH LOAD command potentiometer is failed

Triggered when the Tractor Data Bus signals that the load command potentiometer has failed or is providing an out-of-range voltage signal. This code frequently appears on tractors that do not actually have the hitch load control feature installed, often triggered if a potentiometer or short was mistakenly connected to the armrest connector (J205) during calibration.

• New Holland T9000 Series
• New Holland T8000 Series
• New Holland T8010
• New Holland T8020
• New Holland T8030
• New Holland T8040
• New Holland T8050
• New Holland TG Series
• New Holland TG210
• New Holland TG230
• New Holland TG255
• New Holland TG285
• New Holland T70 Series
• New Holland MXM Series
• New Holland TM Series

1. 1

   Verify if the tractor is actually equipped with the hitch load control (Draft control) feature, as this code frequently triggers falsely on unequipped machines.

2. 2

   If the tractor is NOT equipped with the feature, check for phantom connections and ensure absolutely nothing is plugged into connector J205.

3. 3

   If the tractor IS equipped with the feature, inspect Connector J205 inside the armrest controller housing (Pin 1: high, Pin 2: signal, Pin 3: low).

4. 4

   If equipped, enter the armrest diagnostic/calibration menu and check if the potentiometer is registering a valid voltage range when the dial is swept.

1. 1

   Open the armrest controller housing.

   If the tractor is NOT equipped with Hitch Load (Draft) Control, start by opening the housing.

2. 2

   Verify that nothing is connected to connector J205.

   Remove any debris, moisture, or dummy plugs that might be bridging the pins.

3. 3

   Enter the instrumentation controller to perform the armrest hitch menu calibration procedure.

4. 4

   Select 'No Draft' when prompted for the hitch load command potentiometer during calibration.

5. 5

   Press the PROG key to save.

   The hitch will now be configured as a 'position-only' hitch, and the ARM 79 code will clear.

6. 6

   Access the armrest controller and locate the J205 connector wiring harness.

   If the tractor IS equipped with Hitch Load (Draft) Control, start here.

7. 7

   Inspect the wiring between the hitch load command potentiometer and the J205 connector.

   Look for chafing, pin push-out, or corrosion.

8. 8

   Test the potentiometer for a smooth resistance sweep using a multimeter.

   If the sensor has an open circuit, short circuit, or dead spots, it has failed.

9. 9

   Replace the failed hitch load command potentiometer.

10. 10

    Re-enter the armrest calibration menu and sweep the new potentiometer.

    Ensure the display registers an asterisk (*), indicating the potentiometer is in a valid range.

11. 11

    Press the PROG key to record the voltage and complete the calibration.