Fendt 9.3.12 – E-box: Front EPC, 'Lower' function — Fault in signal line to valve

The tractor's electronic control system has detected a signal line error or electrical fault in the circuit controlling the solenoid valve responsible for the 'Lower' function of the Front Electronic Power Control (EPC / EHR) hitch. The front EPC control is immediately terminated and locked out for safety.

• 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
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III)
• Fendt 700 Vario (COM III)
• Fendt 800 Vario (COM III)
• Fendt 900 Vario (COM III, S4)
• Favorit 916 Vario
• Favorit 920 Vario
• Favorit 924 Vario
• Favorit 926 Vario
• Favorit 930 Vario

1. 1

   Inspect the wiring harness and connectors running from the E-box to the front EPC hydraulic valve block for chafed wires, corrosion, or loose pins

2. 2

   Test the resistance and continuity of the front EPC 'Lower' solenoid valve using a multimeter, comparing readings against the 'Raise' solenoid to identify an open or shorted coil

3. 3

   Back-probe the signal line at the valve connector while commanding a lower function to verify if the E-box is sending the correct voltage signal

4. 4

   Check for accompanying CAN bus or E-box fault codes (e.g., 00.0.0A or 00.0.0B) to verify if the fault lies within the E-box final stage driver

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery to prevent electrical spikes during repair.

2. 2

   Relieve Hydraulic Pressure

   Ensure the front hitch is fully lowered and mechanically supported, and relieve any residual hydraulic pressure in the front EPC circuit.

3. 3

   Repair Wiring

   If the diagnostic checks revealed a broken or shorted signal wire, repair the harness using weatherproof splices or replace the damaged connector pigtail.

4. 4

   Replace Solenoid Valve

   Disconnect the electrical connector from the faulty 'Lower' solenoid valve on the front EPC block. Unthread the retaining nut and remove the solenoid coil, or remove the entire cartridge valve assembly depending on the specific block design. Install the new OEM solenoid valve/coil and torque to manufacturer specifications. Reconnect the electrical harness.

5. 5

   E-box Replacement/Programming

   If the E-box is diagnosed as faulty, it must be replaced and flashed/programmed with EOL (End of Line) software using the FENDIAS diagnostic tool.

6. 6

   Clear Codes and Calibrate

   Reconnect the battery, clear the stored 9.3.12 fault code, and perform the Front EPC calibration procedure (Code 9001 for depth control and Code 9002 for position control) via the tractor's terminal.