Case IH 520585-06 - BCM – BCM: Right brake indicator light - short circuit to ground

The system has detected that the voltage supply wire for the right brake indicator light is making direct contact with a ground source (such as the tractor chassis or a ground wire) before reaching the load, or the light assembly itself has failed internally. The module shuts down the circuit to prevent excessive current draw and wiring damage.

• MAGNUM AFS Connect
• Magnum 180 AFS Connect
• Magnum 200 AFS Connect
• Magnum 240 AFS Connect
• Magnum 250 AFS Connect
• Magnum 280 AFS Connect
• Magnum 310 AFS Connect
• Magnum 340 AFS Connect
• Magnum 380 AFS Connect
• Magnum 400 AFS Connect

1. 1

   Disconnect the right brake indicator light assembly and use a multimeter to check if the short to ground is still present on the harness side to isolate the component.

2. 2

   Visually inspect the wiring harness running from the BCM to the right brake indicator light for chafing, pinched wires, or melted insulation.

3. 3

   Inspect the BCM connectors and the brake light switch connectors for water intrusion, corrosion, or bent pins.

4. 4

   Test the brake light switch for internal faults using a multimeter to ensure it is not shorting the circuit when depressed.

1. 1

   Safely Prep the Machine

   Park the tractor on a level surface, set the parking brake, turn off the ignition, and disconnect the negative battery cable to prevent further electrical damage during testing.

2. 2

   Access the Light Assembly

   Remove the lens or housing for the right brake indicator light. Disconnect the electrical pigtail.

3. 3

   Test the Circuit

   Reconnect the battery temporarily. Using a digital multimeter set to DC volts/continuity, probe the power supply wire at the connector. If it shows continuity to ground (0 ohms) while disconnected from the light, the short is in the wiring harness.

4. 4

   Repair the Wiring (If Applicable)

   Trace the harness back toward the BCM. Once the chafed or pinched section of the wire is located, cut out the damaged section, splice in a new piece of appropriately gauged wire, and seal it with marine-grade heat-shrink tubing.

5. 5

   Replace the Component (If Applicable)

   If the wiring tests fine, the short is internal to the right brake indicator light assembly or the brake light switch. Replace the faulty component.

6. 6

   Reassembly and Clearing Codes

   Reconnect all electrical plugs. Reconnect the battery. Turn the ignition on and use the AFS Pro 1200 monitor or a diagnostic service tool to clear the BCM fault codes.

7. 7

   Verify Repair

   Depress the brake pedals and verify that the right brake indicator light functions properly without triggering a new 520585-06 code.