Fendt 1.2.81 – EDC (Electronic Diesel Control) Engine Control Unit or EMR (Engine Control Module): Signal fault from the B038 or B055 EDC foot throttle rotary position sensor

Signal out of range, signal too high/low, or signal missing from the B038 or B055 EDC foot throttle rotary position sensor. The tractor registers a 'Pedal position sensor signal wrong' error, and the system may switch to an emergency operating mode (loss of enhanced control functions, restricting engine speed control).

• 409 Vario
• 410 Vario
• 411 Vario
• 412 Vario
• 711 Vario
• 712 Vario
• 714 Vario
• 715 Vario
• 716 Vario
• 717 Vario
• 718 Vario
• 916 Vario
• 920 Vario
• 924 Vario
• 926 Vario
• 930 Vario
• Favorit 900 series
• 936 Vario
• 815 Vario
• 817 Vario
• 818 Vario
• 300 Vario

1. 1

   Check the wiring harness for interruptions, short circuits, or power supply failures between the foot throttle sensor and the EDC control module

2. 2

   Inspect the sensor connector (e.g., X176) for corrosion, moisture, or loose pins. Verify the 3-pin connections (Pin 1: Earth, Pin 2: 5V supply, Pin 3: Signal)

3. 3

   With the ignition 'ON' and an adaptor box connected, check the voltage at the EDC Control Module. Idle Position: 0.3 V - 0.6 V, Full Power Position: 4.0 V - 4.5 V

4. 4

   Check the mechanical linkage between the pedal and the sensor to ensure it is not binding or out of adjustment

1. 1

   Turn off the ignition and disconnect the battery

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

2. 2

   Access the foot throttle assembly

   Access the foot throttle assembly in the cab.

3. 3

   Disconnect the electrical connector

   Disconnect the electrical connector from the B038/B055 rotary position sensor.

4. 4

   Repair wiring or replace connector pins

   If wiring damage was found during diagnostics, repair the harness or replace the damaged connector pins.

5. 5

   Remove the faulty potentiometer

   If the wiring and voltages tested fine but the sensor output is out of range, remove the mounting screws/bolts securing the sensor (or the entire pedal assembly, depending on the exact part revision) and remove the faulty potentiometer.

6. 6

   Install the new sensor/pedal assembly

   Install the new OEM foot throttle sensor/pedal assembly and secure the fasteners.

7. 7

   Reconnect the electrical connector and restore battery power

   Reconnect the electrical connector and restore battery power.

8. 8

   Calibrate the new sensor

   The new sensor must be calibrated. Use the tractor's Vario terminal or SERDIA diagnostic software to perform the manual throttle/foot throttle calibration (Calibration code 4005).

9. 9

   Clear fault codes and test drive

   Clear the fault codes from the EDC memory and test drive the tractor to ensure full RPM range is restored.