Fendt 1E.1.12 – Engine Control Unit (ECU) / EDC 7: Pin 50, Ignition starter switch sticking

The ignition switch is mechanically or electrically stuck in the 'Start' (cranking) position, sending a continuous Terminal 50 signal to the engine control system.

• 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 300 Vario (COM III)
• Fendt 400 Vario (COM III)
• Fendt 700 Vario (COM III)
• Fendt 800 Vario (COM III)
• Fendt 900 Vario (COM III)
• Farmer 400
• Favorit 700
• Favorit 900

1. 1

   Physical Inspection: Locate the ignition switch (S002) on the right side of the steering column. Turn the key to the 'Start' position and release it. Verify if the internal spring mechanism is broken, causing the key to hang in the start position rather than springing back to 'On'.

2. 2

   Electrical Testing: Access the separation points/connectors for the ignition switch, designated as X072 and X246. Check for internal short circuits across the switch terminals.

3. 3

   Wiring Check: Verify the wiring harness for Pin 50 between the ignition switch and the EDC to ensure the wire is not shorted to a power source, which would mimic a stuck switch.

1. 1

   Disconnect Power

   Disconnect the tractor's battery to prevent accidental engine cranking or electrical shorts during the repair.

2. 2

   Access the Switch

   Remove the steering column covers or the right-side dashboard paneling to expose the rear of the ignition switch (S002).

3. 3

   Disconnect Wiring

   Unplug the wiring harness connectors (X072 and X246) from the back of the ignition switch.

4. 4

   Remove the Switch

   Unscrew the retaining bezel/nut on the front of the steering column and pull the faulty ignition switch out from the rear.

5. 5

   Install the New Part

   Insert the replacement ignition switch, secure the front retaining bezel, and plug in the X072 and X246 connectors.

6. 6

   Reassemble

   Reinstall the steering column covers and dashboard panels.

7. 7

   Test

   Reconnect the battery. Turn the key to verify it springs back from the start position correctly and starts the tractor.

8. 8

   Clear Codes

   Connect the Fendt SERDIA diagnostic tool to the tractor and clear the stored EDC faults (FC: 00E3, 00E4).