Case IH 520580-06 - BCM – BCM: Turn light front right - short circuit to ground

The power wire supplying voltage to the front right turn signal is making direct contact with the chassis ground (or the ground wire) before the electrical load, causing a short circuit.

• MAGNUM AFS Connect
• Magnum
• Puma
• Steiger
• Maxxum
• Farmall
• Quadtrac
• 570N
• 580N
• 580 Super N
• 580L
• 580M
• 590 Super N

1. 1

   Inspect the front right turn signal housing and lens for physical damage, water ingress, or a melted bulb socket (common cause of internal shorts).

2. 2

   Trace the wiring harness from the front right turn light back toward the BCM. Look for pinched wires, chafing against the frame, or melted insulation exposing bare copper to the chassis.

3. 3

   Disconnect the electrical plug at the front right turn signal. Turn the ignition on and activate the right turn signal. If the fault code changes to an 'open circuit' code, the short is internal to the light assembly. If the short circuit code remains, the wiring harness is shorted to the frame.

4. 4

   With the battery disconnected, use a multimeter to check for continuity between the turn signal power wire (on the harness side) and a solid chassis ground. Near 0 ohms indicates a wiring short.

1. 1

   Power Down

   Turn off the ignition and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Access the Light

   Locate the front right turn signal assembly (often mounted on the cab corner, fender, or front grill depending on the model).

3. 3

   Repair the Wiring (If Applicable)

   If your diagnostic checks revealed a chafed wire touching the frame, cut out the damaged section. Splice in a new section of wire using weatherproof heat-shrink butt connectors. Wrap the repaired section in protective wire loom and secure it away from pinch points with zip ties.

4. 4

   Replace the Light Assembly (If Applicable)

   If the short is internal to the light housing, remove the mounting bolts/nuts securing the light assembly. Disconnect the pigtail connector and remove the old unit.

5. 5

   Install the New Part

   Mount the replacement turn signal assembly and plug in the electrical connector. Ensure the weather seal on the connector is intact.

6. 6

   Test and Clear Codes

   Reconnect the battery. Turn the ignition on and test the right turn signal. Use the tractor's diagnostic display or a service tool to clear the inactive 520580-06 fault code from the BCM.