Fendt A020 – EDC: Pump Control Failure

The engine's ECU has detected a communication or operational fault with the pump control unit (injection pump) within the Electronic Diesel Control (EDC) system. This indicates a disruption in CAN communication between the main ECU and the injection pump, an internal signal processing or RAM fault, deviations in the injection start system or the injection controller being out of its specified range, or a fault related to the propagation time of CAN messages between the pump control unit and the EDC control module (A021). This fault typically results in reduced engine power, engine stalling, or a failure to start.

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

1. 1

   Retrieve all fault codes from the diagnostic menu to identify concurrent power supply, sensor, or communication bus errors

2. 2

   Check the fuel supply system for air leaks, clogged fuel filters, or a problematic fuel separator/filter to rule out basic delivery issues mimicking electronic faults

3. 3

   Inspect the wiring harness and electrical connectors between the main EDC control module (A021) and the injection pump control unit (A020) for damage, corrosion, or loose connections

4. 4

   Verify the power supply to the EDC system by checking relevant fuses and relays (e.g., Ub30 EDC relay)

5. 5

   Assess for related sensor failures, specifically the needle movement sensor (B026) or the engine speed sensor (B025)

1. 1

   Address basic fuel and electrical issues

   Rectify any identified fuel system blockages, air leaks, or electrical connection problems. Clear the fault codes and operate the machine to verify if the fault returns.

2. 2

   Perform component-specific diagnosis

   If the fault persists and sub-codes point to a specific part of the pump (such as the electronic volume controller or speed sensor), test these components. Note that these are often integral to the injection pump and cannot be serviced separately.

3. 3

   Replace injection pump assembly

   If diagnostics confirm an internal failure of the pump control unit (A020), replace the entire electronic injection pump assembly (e.g., Bosch VP44). After replacement, program and calibrate the new unit using Fendt's diagnostic tools (FENDIAS).