John Deere 2354.03 – BLC (Basic Lighting Controller): Front Corner Worklights, External Voltage (Short to Power)

The controller is detecting voltage on the front corner (bonnet/grille) work light circuit when the lights are commanded OFF. This indicates a voltage backfeed, meaning the circuit is shorted to a constant power source (like battery positive or another active lighting circuit) somewhere in the wiring loom, or the module itself has an internal fault keeping the circuit live.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6090MC
• 6090RC
• 6100MC
• 6100RC
• 6110MC
• 6110RC
• 944K Loader
• 310SK Backhoe

1. 1

   Verify the symptom: Turn the work lights off at the cab switch and check if the front corner bonnet lights remain illuminated or if the code stays active.

2. 2

   Isolate the harness vs. module: Disconnect the front corner work lights at their pigtail connectors and use a multimeter to check for voltage at the harness pins.

3. 3

   Check for loom backfeed: If voltage is present with the switch off, disconnect the lighting harness directly at the BLC module. If the voltage on the harness side disappears, the BLC module likely has an internal short. If voltage remains on the harness side, there is a physical short-to-power in the wiring loom.

4. 4

   Inspect the wiring loom: Trace the front lighting harness, paying close attention to pinch points near the bonnet hinges, grille mounts, and tight bends. Look for chafed wire insulation, melted wires, or aftermarket accessories improperly spliced into the lighting circuit.

1. 1

   Disconnect Power

   Disconnect the negative battery terminal to prevent accidental arcing or further module damage during the repair.

2. 2

   Repair the Wiring Loom (If shorted)

   If a short was found in the harness during diagnostics, cut out the damaged section of the wire. Splice in a new section of appropriately gauged wire using weatherproof crimp connectors and heat-shrink tubing. Tape and re-loom the harness to protect it from future chafing.

3. 3

   Replace the Work Light (If internally shorted)

   If the work light housing is damaged or internally shorted, unbolt the mounting bracket, disconnect the pigtail, and mount the replacement light.

4. 4

   Replace the BLC Module (If faulty)

   If the BLC module is internally shorted and sending power when commanded off, it must be replaced. Locate the BLC, disconnect the multi-pin connectors, and swap the module. (Note: A new BLC module may require software calibration/programming via John Deere Service ADVISOR).

5. 5

   Test and Clear Codes

   Reconnect the battery. Turn the ignition on and test the work light switch. Ensure the lights turn on and off correctly, and use a diagnostic tool to clear the inactive 002354.03 code.