Fendt 0F.1.08 – Central Electrical System ECU (A038): H4 Additional Headlight Malfunction

The system detects an unknown error in the central electrical system related to the additional H4 headlights (E003 right, E004 left), typically indicating an open circuit, blown bulbs, or a wiring fault. As a safety measure, the additional headlights become non-operable and the tractor's electrical system automatically switches over to the standard front headlights.

• 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
• Fendt 309 Vario
• Fendt 310 Vario
• Fendt 311 Vario
• Fendt 312 Vario
• Fendt 400 Vario
• Fendt 700 Vario
• Fendt 800 Vario
• Fendt 900 Vario
• Fendt 916 Vario
• Fendt 922 Vario
• Fendt 924 Vario
• Fendt 926 Vario
• Fendt 927 Vario
• Fendt 930 Vario
• Fendt 933 Vario
• Fendt 936 Vario

1. 1

   Check the H4 halogen bulbs in both the left and right additional headlight housings to see if the filaments are burnt out.

2. 2

   Disconnect the headlight connectors and use a multimeter to check for voltage. When the lights are switched ON, the main beam (terminal 56a) and dipped beam (terminal 56b) should both read approximately 14 VDC. When OFF, they should read 0 VDC.

3. 3

   Inspect the specific separation points for these lights: X352 (for the right headlight E003) and X353 (for the left headlight E004). Look for corrosion, moisture ingress, or loose pins.

4. 4

   Verify the fuses and relays in the central electrical board, as the fault points to a central electrical system error.

1. 1

2. 2

   Safely park the tractor

   Turn off the engine, engage the parking brake, and turn off the battery disconnect switch to prevent short circuits while working on the electrical system.

3. 3

   Access the headlights

   Remove the retaining screws or clips holding the additional H4 headlight housings (E003 and E004) in place.

4. 4

   Replace the bulbs

   If the diagnostic checks revealed blown bulbs, replace them with standard 12V 60/55W H4 halogen bulbs. Do not touch the glass of the new bulbs with bare hands, as oil from your skin can cause premature failure.

5. 5

   Clean connectors

   If the bulbs are intact but voltage was missing or intermittent, clean the X352 and X353 connectors with electrical contact cleaner and apply dielectric grease to prevent future corrosion.

6. 6

   Repair wiring

   If continuity testing showed a break between the central electrical system (A038) and the headlights, locate the damaged wire section and splice in a new wire using waterproof heat-shrink connectors.

7. 7

   Test and clear codes

   Reconnect the battery, turn on the tractor, and test the additional headlights. Use the tractor's terminal or the FENDIAS diagnostic tool to clear the stored 0F.1.08 fault code.