John Deere 2350.03 – VLC (Vehicle Load Controller) or VCU (Vehicle Control Unit): Low Beam Lights Circuit Voltage High

The controller is detecting a higher voltage than expected on the low beam headlight circuit, which typically indicates a "Short to Power" fault in the wiring or the component itself.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8R Series (8245R to 8400R)
• 8RT Series
• 8RW Series
• 9RT Series (9470RT, 9520RT, 9570RT)
• 6R Series
• 7R Series
• 250D
• 300D
• 260E
• 310E
• 310SK
• 315SK
• 770G
• 770GP
• 772G
• 772GP
• 544K Series II
• 944K Hybrid 4WD Loader

1. 1

   Visually inspect the wiring harness running from the VLC (or VCU) to the front low beam headlights/drive lights for chafed insulation, pinched wires, or areas rubbing against a power source.

2. 2

   Disconnect the headlight connectors and the VLC harness connectors to inspect for bent pins, corrosion, or moisture that could bridge a power circuit to the low beam pin.

3. 3

   Use a multimeter to test the low beam circuit for a short to power. With the lights commanded off, check if voltage is still present at the headlight connector.

4. 4

   Disconnect the headlights to isolate the component. If the short to power remains, the fault is in the wiring harness or the VLC. If the short disappears, the headlight assembly itself may be internally shorted.

1. 1

   Disconnect Power

   Always disconnect the battery before servicing electrical circuits to prevent further damage to the VLC or wiring.

2. 2

   Isolate the Short

   Based on your diagnostic checks, trace the specific section of the wiring harness that is shorting to power.

3. 3

   Repair Wiring

   If a wire is chafed and touching a 12V/24V source, repair the wire using OEM-approved splicing methods and heat-shrink tubing. Reroute the harness away from sharp edges or heat sources.

4. 4

   Replace Components (if necessary)

   If the wiring is intact but the headlight assembly is internally shorted, replace the headlight unit. If the VLC pin is permanently outputting high voltage due to an internal failure, the VLC module will need to be replaced and reprogrammed by a dealer.

5. 5

   Test

   Reconnect the battery, clear the 002350.03 fault code, and cycle the low beam headlights to verify the repair.