Case IH 4011-05 - BCM – BCM: Left High Beam Open Circuit

The Body Control Module (BCM) has detected a break in the electrical circuit for the left high beam headlamp, preventing current from flowing. This open circuit condition is most commonly caused by a blown bulb filament, a disconnected plug, or a severed wire in the lighting harness.

• MAGNUM AFS Connect
• Steiger AFS Connect
• Puma AFS Connect

1. 1

   Access the left headlamp assembly and inspect the high beam bulb for a blown filament

2. 2

   Inspect the electrical connector at the left headlamp for loose pins, corrosion, or moisture intrusion

3. 3

   Use a multimeter to check for continuity on the power and ground wires running from the BCM to the left headlamp assembly, looking for chafed, pinched, or broken wires

4. 4

   Verify that the BCM is sending voltage to the left high beam circuit when the high beams are commanded on

1. 1

   Depower circuit

   Turn off the tractor, remove the key, and ensure the lighting circuit is completely unpowered.

2. 2

   Access headlamp

   Open the hood/grille access to reach the rear of the left headlamp assembly.

3. 3

   Disconnect harness

   Disconnect the wiring harness plug from the left high beam bulb.

4. 4

   Test and replace bulb

   Remove the bulb and test it for continuity. If the bulb is blown (most common cause), replace it with a new bulb. Avoid touching the glass of a new halogen bulb with your bare hands.

5. 5

   Inspect and repair wiring

   If the bulb is good, trace the wiring harness back to the BCM. Repair any broken wires or replace damaged connector pigtails using weatherproof heat-shrink butt connectors.

6. 6

   Test system

   Reconnect the headlamp assembly, power on the tractor, and test the high beam function.

7. 7

   Clear fault codes

   Connect a diagnostic tool (such as the Case IH Electronic Service Tool or Jaltest) to clear the inactive 4011-05 fault code from the BCM memory.