Fendt 1E.1.52 – Engine Control Unit (ECU): B086 - Rail pressure sensor (Cable break or short circuit)

Cable break or short circuit in the B086 rail pressure sensor's circuit. When this fault is active, the tractor's display will show a critical warning message stating that the engine will stop in approximately 5 minutes.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• Fendt 309 Vario
• Fendt 310 Vario
• Fendt 311 Vario
• Fendt 312 Vario
• Fendt 409 Vario
• Fendt 410 Vario
• Fendt 411 Vario
• Fendt 412 Vario
• Fendt 711 Vario
• Fendt 712 Vario
• Fendt 714 Vario
• Fendt 716 Vario
• Fendt 815 Vario
• Fendt 817 Vario
• Fendt 818 Vario
• Fendt 819 Vario
• Fendt 822 Vario
• Fendt 824 Vario
• Fendt 826 Vario
• Fendt 828 Vario
• Fendt 916 Vario
• Fendt 920 Vario
• Fendt 922 Vario
• Fendt 924 Vario
• Fendt 927 Vario
• Fendt 930 Vario
• Fendt 933 Vario
• Fendt 936 Vario
• Fendt 939 Vario

1. 1

   Wait at least 30 seconds after switching off the diesel engine before starting any work on the fuel system to allow the high-pressure accumulator (rail) to depressurize safely

2. 2

   Visually inspect the wiring harness leading to the B086 rail pressure sensor for chafed wires, melted insulation, or a disconnected plug

3. 3

   Disconnect the 3-pin connector at the B086 sensor and check for corrosion, bent pins, or moisture ingress

4. 4

   Verify that the sensor is receiving the correct reference voltage from the Engine ECU and that the signal wire has continuity back to the ECU pins

1. 1

   Turn off the tractor ignition and wait 30 seconds for the fuel rail pressure to drop.

   Wait 30 seconds for the fuel rail pressure to drop.

2. 2

   Locate the B086 Rail pressure sensor, which is threaded directly into the high-pressure fuel accumulator (common rail).

   Locate the B086 Rail pressure sensor.

3. 3

   If the diagnostic checks revealed damaged wiring, repair the harness or replace the connector pigtail.

   Repair the harness or replace the connector pigtail if wiring is damaged.

4. 4

   If the wiring and voltages test fine, the internal circuitry of the B086 sensor has likely failed. Unplug the electrical connector and use a wrench to carefully unthread the faulty sensor from the fuel rail.

   Unplug the electrical connector and unthread the faulty sensor from the fuel rail.

5. 5

   Install the new rail pressure sensor and torque it to the manufacturer's specification. Reconnect the wiring harness.

   Install the new rail pressure sensor, torque to spec, and reconnect the wiring harness.

6. 6

   Connect a diagnostic laptop with SERDIA (Deutz/Fendt diagnostic software) to the machine.

   Connect a diagnostic laptop with SERDIA.

7. 7

   Clear the stored fault codes (specifically FC:00D1 and 00D2, which are the sub-codes associated with 1E.1.52).

   Clear the stored fault codes.

8. 8

   Start the engine and verify that the fuel pressure reads normally (typically between 400 bar at idle and up to 1600-1800 bar under load) and that the 5-minute shutdown warning does not return.

   Start the engine and verify normal fuel pressure and absence of the shutdown warning.