Massey Ferguson 0.0.4B – Dash (Instrument Panel): Issue With Hand Throttle Circuit, Open Circuit (Dash)

The system has detected an "open circuit" in the hand throttle control circuit. This means the electrical connection between the hand throttle potentiometer and the control module is broken, unplugged, or the internal resistance of the potentiometer has failed open, preventing the module from reading the operator's throttle input.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S

1. 1

   Inspect the hand throttle lever assembly on the right-hand console for physical damage to the lever or the wiring pigtail exiting the base.

2. 2

   Disconnect the plug at the hand throttle potentiometer and check for dust contamination, moisture, or corroded pins.

3. 3

   Using a multimeter, check the continuity of the wiring harness from the hand throttle connector back to the Dash/Instrument Panel module for chafed wires or broken solder bonds.

4. 4

   Measure the resistance across the pins of the hand throttle potentiometer while slowly moving the lever. The resistance should change smoothly without reading 'OL' (Open Loop).

1. 1

   Power Down

   Turn off the ignition and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Access the Throttle Assembly

   Remove the trim panels on the right-hand console/pillar to expose the base of the hand throttle mechanism.

3. 3

   Disconnect

   Unplug the electrical connector from the hand throttle potentiometer.

4. 4

   Replace the Component

   If the wiring harness is damaged, repair the broken wire and apply a protective heat-shrink seal to shield it from dust and moisture. If the potentiometer failed the multimeter test, unbolt the faulty hand throttle potentiometer/switch from the console bracket and install the new OEM replacement.

5. 5

   Reassembly

   Reconnect the electrical plug, ensuring it clicks securely into place. Reinstall the console trim panels.

6. 6

   Clear Codes

   Reconnect the battery, turn the ignition on, and verify that the Dash module registers the hand throttle movement. Clear the 0.0.4B fault code using a diagnostic scan tool or the tractor's onboard diagnostic menu.