Massey Ferguson 03.02.9D – MFA (Multifunction Armrest): Issue With Hand Throttle On Arm Rest Signal Voltage

The system has detected an irregular or out-of-range electrical signal voltage coming from the hand throttle potentiometer (sensor). This prevents the tractor's engine control system from accurately determining the operator's requested engine speed via the hand throttle.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 8600 Series

1. 1

   Inspect the wiring harness connecting the hand throttle potentiometer to the MFA controller inside the armrest for pinched wires, chafing, or loose/corroded connector pins.

2. 2

   Perform a voltage sweep test using a multimeter or the AGCO Electronic Diagnostic Tool (EDT) to monitor the signal voltage while slowly moving the throttle from minimum to maximum position. The voltage should change smoothly without dropping out or spiking.

3. 3

   Attempt to recalibrate the throttle limits via the dashboard terminal (Calibration Code 4002).

1. 1

   Power Down

   Turn off the ignition and disconnect the tractor's battery to prevent electrical shorts.

2. 2

   Access the Sensor

   Remove the retaining screws on the Multifunction Armrest (MFA) casing to access the internal control components.

3. 3

   Remove the Old Sensor

   Locate the hand throttle assembly. Disconnect the electrical harness plug from the potentiometer. Remove the mounting screws/clips holding the throttle unit in place and extract it.

4. 4

   Install the New Sensor

   Seat the new hand throttle potentiometer into the armrest housing, secure the mountings, and plug in the electrical connector.

5. 5

   Reassemble

   Reinstall the armrest covers and reconnect the battery.

6. 6

   Calibrate the New Sensor

   Turn the ignition ON. Enter the tractor's calibration menu (Calibration 4002). You will be prompted to move the hand throttle to the maximum position and press 'Return/Confirm', then move it to the minimum position and press 'Return/Confirm'. Wait for the 'O.K.' prompt and cycle the ignition key to the '0' position to save the new sensor voltage parameters.