Fendt 1E.1.23 – A051 - ECU, engine control unit (EDC 7): Cable break or short circuit in S047 engine brake switch circuit

The system has detected a cable break or short circuit in the wiring circuit for the engine brake switch (S047).

• 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
• 300 Vario (COM III)
• 309 Vario (COM III)
• 310 Vario (COM III)
• 311 Vario (COM III)
• 312 Vario (COM III)
• 400 Vario (COM III)
• 500 Vario s4 Series
• 700 Vario (COM III)
• 800 Vario (COM III)
• 900 Vario (COM III)
• 916 Vario (COM III)
• 920 Vario (COM III)
• 922 Vario (COM III)
• 924 Vario (COM III)
• 926 Vario (COM III)
• 927 Vario (COM III)
• 930 Vario (COM III)
• 933 Vario (COM III)
• 936 Vario (COM III)
• 939 Vario (COM III)

1. 1

   Read out the fault memory using the Fendt SERDIA program to verify active fault code (FC:0034) and check for related codes (1E.1.24 or 1E.1.25).

2. 2

   Check separation point X140 on the S047 switch circuit, typically located in the cab on the floor to the left.

3. 3

   Inspect the wiring harness between the S047 engine brake switch and the A051 EDC engine control unit for continuity, pinched wires, chafing, or disconnected pins.

4. 4

   Test the S047 switch using a multimeter for proper open/closed operation when the engine brake is actuated.

1. 1

   Power Down

   Turn off the tractor ignition and disconnect the battery to prevent electrical spikes during repair.

2. 2

   Access the Switch

   Locate the S047 engine brake switch (typically floor-mounted in the cab).

3. 3

   Repair Wiring (If Applicable)

   If the diagnostic continuity test revealed a broken wire or short circuit between separation point X140 and the EDC, repair the damaged section of the wiring harness using OEM-approved waterproof splices or replace the affected harness section.

4. 4

   Replace the Switch (If Applicable)

   If the wiring is intact but the switch failed the multimeter continuity test, unplug the connector at X140, unbolt the faulty S047 switch, and install the replacement part.

5. 5

   Clear Codes

   Reconnect the battery, turn on the ignition, and use the SERDIA diagnostics program to delete the error (FC:0034) from the EDC memory.

6. 6

   Functional Test

   Run the engine and test the engine brake to ensure proper operation and verify that the fault code does not return.