Massey Ferguson 00.X.4B – Dash (Instrument Panel / Dashboard Module): Issue With Hand Throttle Circuit, Open Circuit

The electrical signal from the hand throttle potentiometer has been lost. An 'open circuit' typically means there is a broken wire, an unplugged connector, or the internal potentiometer/sensor has failed completely, preventing the signal from reaching the controller.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626

1. 1

   Access the right-hand console and visually inspect the electrical connector at the hand throttle potentiometer for loose, corroded, or backed-out pins.

2. 2

   Trace the wiring harness from the hand throttle switch back to the Dash module and use a multimeter to check for continuity to rule out a broken or chafed wire.

3. 3

   Test the hand throttle potentiometer switch for a smooth resistance or voltage sweep. If the sensor reads completely open (infinite resistance) across its sweep, the sensor itself has failed internally.

1. 1

   Power Down

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

2. 2

   Access the Console

   Remove the trim panels on the right-hand operator console to expose the underside of the hand throttle assembly.

3. 3

   Disconnect

   Unplug the electrical connector from the hand throttle potentiometer switch.

4. 4

   Wiring Repair (If Applicable)

   If your diagnostic checks revealed a broken wire in the harness, splice and repair the wire using OEM-approved heat-shrink connectors.

5. 5

   Component Replacement

   If the wiring is intact and the sensor is faulty, unbolt the hand throttle potentiometer switch assembly from the console and install the replacement unit.

6. 6

   Reassembly

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

7. 7

   Clear Codes

   Reconnect the battery, turn the ignition on, and use a diagnostic tool to clear the 00.X.4B fault code. Test the hand throttle to ensure engine RPM responds correctly.