Case IH 520577-05 - BCM – BCM: Right side rear turn light - open circuit

The control module has detected a break in the electrical path for the rear right turn signal. An "open circuit" means current cannot flow, which is typically caused by a burnt-out bulb, a failed LED assembly, a disconnected plug, or a severed wire in the harness.

• MAGNUM AFS Connect
• Steiger
• Optum

1. 1

   Check the rear right turn signal assembly to see if the bulb is burnt out or if the LED housing is physically damaged

2. 2

   Unplug the rear right turn signal and inspect the pins for heavy oxidation, corrosion, or pushed-out pins that could create an open circuit

3. 3

   Using a multimeter, probe the light connector for 12V power and ground while the right turn signal is activated

4. 4

   If there is no power at the connector, test for continuity along the wiring harness from the rear right light connector back to the BCM output pin to locate the break in the wire

1. 1

   Power Down

   Turn off the tractor, remove the key, and set the parking brake.

2. 2

   Access the Assembly

   Locate the rear right turn signal assembly on the rear fender or cab pillar.

3. 3

   Disconnect and Isolate

   Unplug the electrical connector from the light assembly.

4. 4

   Test the Component

   Swap the right light assembly with the left light assembly (if the connectors are identical) or test the bulb with a multimeter. If the fault moves to the left side or the bulb tests open, the light assembly/bulb is the culprit.

5. 5

   Replace or Repair

   If the bulb/LED is faulty, replace the light assembly. If the light is good but the connector is corroded, clean the contacts with electrical contact cleaner and apply dielectric grease, or splice in a new connector pigtail. If the wire is broken, trace the harness back to the BCM, locate the severed wire, and perform a weatherproof splice repair.

6. 6

   Clear and Verify

   Reconnect the assembly, turn the ignition to the ON position, activate the right turn signal, and verify that the light blinks correctly and the BCM fault code clears from the AFS Pro display.