Fendt 04.1.8A – Transmission Control Unit (TCU): B017, S074 - Sensor, clutch pedal

A plausibility error regarding the electrical clutch pedal. The Transmission Control Unit detects that the signals from the clutch pedal rotary position sensor (B017) and the starter lockout/clutch pedal limit switch (S074) do not logically match, specifically because the TK line (or TC cable) is not opened when the clutch pedal is depressed.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• 207 200 V/F/P Vario
• 208 200 V/F/P Vario
• 209 200 V/F/P Vario
• 210 200 V/F/P Vario
• 211 200 V/F/P Vario
• 309 300 Vario COM III
• 310 300 Vario COM III
• 311 300 Vario COM III
• 312 300 Vario COM III
• 409 400 Vario
• 410 400 Vario
• 411 400 Vario
• 412 400 Vario
• 711 700 Vario / SCR
• 712 700 Vario / SCR
• 714 700 Vario / SCR
• 716 700 Vario / SCR
• 718 700 Vario / SCR
• 720 700 Vario / SCR
• 722 700 Vario / SCR
• 724 700 Vario / SCR
• 815 800 Vario
• 817 800 Vario
• 818 800 Vario
• 916 900 Vario / S4 / COM III
• 920 900 Vario / S4 / COM III
• 924 900 Vario / S4 / COM III
• 926 900 Vario / S4 / COM III
• 930 900 Vario / S4 / COM III
• 933 900 Vario / S4 / COM III
• 936 900 Vario / S4 / COM III
• 939 900 Vario / S4 / COM III

1. 1

   Check the TK Line / TC Cable wiring between the clutch pedal and transmission ECU for short circuits to ground or chafed wires.

2. 2

   Test the starter lockout/clutch pedal limit switch (S074) for continuity to ensure it breaks the circuit when the pedal is pressed.

3. 3

   Monitor the clutch pedal rotary position sensor (B017) via the diagnostic terminal for drifting, altered, or failing calibration values.

4. 4

   Verify the 8.5V supply to the transmission sensors and check for a blown fuse (e.g., A013 Fuse 8).

1. 1

   Access the Pedal Assembly

   Locate the clutch pedal assembly inside the cab to access sensor B017 and switch S074.

2. 2

   Inspect and Repair Wiring

   If the TK line is shorted, repair the damaged section of the wiring harness and secure it away from pinch points.

3. 3

   Replace Faulty Components

   If switch S074 fails the continuity test, unbolt it from the pedal bracket, disconnect the harness, and install a new switch. If sensor B017 shows erratic or no voltage sweep, remove its retaining hardware, disconnect the plug, and install a new rotary position sensor.

4. 4

   Clear Codes and Test

   Turn the key on, clear the active 04.1.8A fault code from the tractor's memory, and depress the clutch pedal to ensure the TK line opens correctly and the code does not return.

5. 5

   Calibration

   If transmission control components were replaced, run the transmission calibration routine (Calibration code '4001') via the onboard terminal.