Fendt 1.2.37 – A051 - ECU, Engine Control Unit (EDC 7): Fan speed above setpoint range

The engine control unit has detected that the cooling fan is spinning faster than the commanded target speed. This typically indicates that the electronically controlled viscous fan clutch has mechanically locked up, or there is a fault with the fan speed sensor/wiring causing an incorrect high-speed reading.

• 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
• 309
• 310
• 311
• 312
• 409
• 410
• 411
• 412
• 711
• 712
• 714
• 715
• 716
• 717
• 815
• 817
• 818
• 820
• 916
• 920
• 924
• 926
• 930
• 936

1. 1

   Clean/change air filter, as severely restricted airflow can alter cooling demands and fan resistance.

2. 2

   Check the wiring harness and plug connections between the A051 Engine ECU, the viscous fan clutch, and the fan speed sensor for shorts to power.

3. 3

   Ensure the air gap between the sensor and the fan hub is correct (typically around 3/16" on larger models).

4. 4

   Connect the AGCO 2x4 CANUSB diagnostic tool and use the SERDIA software to compare the 'Target Fan Speed' against the 'Actual Fan Speed'.

1. 1

   Clear the Fault

   Use the SERDIA diagnostic software to delete the error code (FC: 1.2.37). Run the tractor to see if the code actively returns.

2. 2

   Inspect the Viscous Clutch

   With the engine off, manually inspect the viscous fan clutch. If it is completely seized and cannot be turned by hand, the internal fluid valve has failed, and the clutch must be replaced.

3. 3

   Test the Sensor

   If the fan spins freely when the engine is off but the SERDIA tool shows erratic or pegged fan speeds while running, replace the fan speed sensor.

4. 4

   Replace the Fan Clutch

   If the wiring and sensor are intact but the fan continues to over-speed (running at a 1:1 ratio with engine RPM), replace the viscous fan drive clutch assembly.

5. 5

   Final Calibration

   After replacing the fan clutch or sensor, clear the fault codes via SERDIA and run the tractor up to operating temperature to ensure the fan modulates correctly.