Fendt 1.2.07 – A051 - ECU, Engine Control Unit (EDC 7): B091 - Sensor, water in fuel

The water level in the fuel filter/water sedimentor is above the setpoint range, or there is a cable break or short circuit in the sensor's wiring.

• 411 Vario COM III
• 412 Vario COM III
• 413 Vario COM III
• 414 Vario COM III
• 415 Vario COM III
• 712 Vario COM III
• 714 Vario COM III
• 716 Vario COM III
• 718 Vario COM III
• 818 Vario COM III
• 820 Vario COM III
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III) (Models 409, 410, 411, 412)
• Fendt 700 Vario (COM III) (Models 711, 712, 714, 715, 716, 717)
• Fendt 800 Vario (COM III) (Models 815, 817, 818)
• Fendt 900 Vario (COM III) (Models 916, 920, 924, 926, 927, 930, 933, 936, 939)

1. 1

   Check the fuel filter/water separator bowl visually to see if water has accumulated above the maximum target range.

2. 2

   Inspect the wiring harness and connections for a cable break or short circuit, specifically checking the X1660 separation point on the B091 sensor (on 900 Vario models, this is located on the right side behind the right fuel tank and requires removing the central control block panel).

3. 3

   Test the sensor signal: the sensor operates as a switch (open when water level is OK, closed when water level is too high).

1. 1

   Drain the Water

   Open the drain valve on the fuel filter/water sedimentor and drain the accumulated water into a suitable container.

2. 2

   Retest

   Turn the ignition on to see if the fault code clears.

3. 3

   Repair Wiring

   If the code persists and the filter is empty, trace the wiring back to the A051 Engine Control Unit using Circuit Diagram Sheet 36 (or Sheet 22 depending on the specific model year) to repair any shorts or breaks.

4. 4

   Clear the Fault

   Once the physical repair is complete, the error must be permanently deleted from the engine control unit memory using the SERDIA diagnostic software (FC:0057 and FC:0059).