Fendt 1E.1.04 – Engine Control Unit (ECU): Coolant temperature sensor (Deutz engine) wiring break or short circuit

The system has detected a break in the wiring or a short circuit at the coolant temperature sensor. As a result, the registered coolant temperature is falling outside the target/setpoint area.

• 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
• 207
• 208
• 209
• 210
• 211
• 309
• 310
• 311
• 312
• 409
• 410
• 411
• 412
• 413
• 415
• 711
• 712
• 714
• 716
• 718
• 815
• 817
• 818
• 916
• 920
• 922
• 924
• 926
• 927
• 930
• 933
• 936
• 939

1. 1

   Read Live Data: Connect the FENDIAS or Deutz SERDIA diagnostic tool and read the KWP/FC codes to confirm FC:0037 or FC:0038.

2. 2

   Wiring Inspection: Check the wiring harness leading to the B089 sensor for physical breaks, chafing, or short circuits.

3. 3

   Connector Check: Inspect the 2-pin connector at the sensor for corrosion, moisture, or loose pins.

4. 4

   Sensor Verification: Check the live coolant temperature reading in the diagnostic software. If it reads an impossible value (e.g., extreme negative or positive max values), the sensor or its circuit is dead.

1. 1

   Preparation

   Ensure the tractor engine is turned off and completely cooled down to prevent severe burns from hot, pressurized coolant.

2. 2

   Locate the Sensor

   Locate the B089 coolant temperature sensor on the Deutz engine block.

3. 3

   Disconnect

   Unplug the 2-pin electrical connector from the sensor.

4. 4

   Removal

   Using a 19mm spanner, carefully unscrew the sensor (Thread size: M14x1.5). Have a rag or catch pan ready, as a small amount of coolant will escape.

5. 5

   Installation

   Install the new sensor with its sealing ring. Do not overtighten.

6. 6

   Reassembly

   Reconnect the 2-pin electrical connector.

7. 7

   Fluid Check

   Top up the engine coolant to the correct level if any was lost during the swap.

8. 8

   Clear Faults

   Connect the SERDIA or FENDIAS diagnostic tool and delete the 1E.1.04 (FC:0037/0038) error from the engine control memory.