John Deere 521544.05 – RLC (Roof Lighting Control / Cab Roof Module): Rear Inner Left Roof Flood Light Current Low

The control module is monitoring the electrical circuit for the rear inner left work light and has detected that the current draw (amperage) is below the minimum expected threshold. This condition is almost always caused by an open circuit, which typically means a blown halogen bulb, a burnt-out LED assembly, a disconnected wiring harness, or a broken wire.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 7R Series
• 7210R
• 7230R
• 7310R
• 8R Series
• 8RT Series
• 8RX Series
• 8245R
• 8400R
• 9R Series
• 9RT Series
• 9RX Series
• 9470RT
• 9520RT
• 9570RT
• 9620RX

1. 1

   Visually inspect the rear inner left work light for obvious physical damage, water intrusion behind the lens, or a shattered bulb.

2. 2

   Disconnect the wiring harness at the light and inspect the pins for corrosion, pushed-back terminals, or moisture, which can cause an open circuit.

3. 3

   Perform a swap test by swapping the rear inner left work light with the rear inner right work light. If the fault code changes to the right side (e.g., 521545.05), the light assembly has failed. If the 521544.05 code remains, the issue lies in the wiring harness or RLC module.

4. 4

   If the fault stays on the left side after the swap test, use a multimeter to check for continuity on the ground wire and verify that 12V is reaching the positive pin when the work lights are commanded on.

1. 1

   Power down the tractor, turn the battery disconnect switch to the OFF position, and remove the key.

   Power down the tractor, turn the battery disconnect switch to the OFF position, and remove the key.

2. 2

   Safely access the rear cab roof using an appropriate ladder or platform.

   Safely access the rear cab roof using an appropriate ladder or platform.

3. 3

   Locate the rear inner left work light. Disconnect the 2-pin electrical connector from the rear of the housing.

   Locate the rear inner left work light. Disconnect the 2-pin electrical connector from the rear of the housing.

4. 4

   Remove the mounting bracket hardware (usually a single carriage bolt and nut) securing the light to the cab roof bracket.

   Remove the mounting bracket hardware (usually a single carriage bolt and nut) securing the light to the cab roof bracket.

5. 5

   Remove the old light assembly.

   Remove the old light assembly.

6. 6

   Mount the new replacement light assembly to the bracket and tighten the hardware to secure it.

   Mount the new replacement light assembly to the bracket and tighten the hardware to secure it.

7. 7

   Apply a small amount of dielectric grease to the electrical connector to prevent future moisture intrusion, then plug it into the new light.

   Apply a small amount of dielectric grease to the electrical connector to prevent future moisture intrusion, then plug it into the new light.

8. 8

   Restore battery power, turn the key to the ON position, and activate the rear work lights.

   Restore battery power, turn the key to the ON position, and activate the rear work lights.

9. 9

   Verify the new light illuminates. Navigate to the CommandCenter display and clear the stored RLC fault codes.

   Verify the new light illuminates. Navigate to the CommandCenter display and clear the stored RLC fault codes.