John Deere 521557.06 – RLC: Front Inner Roof Flood Light Right Current High

The system has detected that the electrical current (amperage) being drawn by the front inner right work light circuit exceeds the maximum allowable threshold. This condition is typically caused by a short circuit to ground within the wiring harness, a failed or internally shorted light assembly (bulb or LED driver), or a malfunction within the control module itself.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8225R
• 8235R
• 8245R
• 8260R
• 8270R
• 8285R
• 8295R
• 8310R
• 8320R
• 8335R
• 8345R
• 8360R
• 8370R
• 8400R
• 9470RT
• 9520RT
• 9570RT

1. 1

   Examine the front inner right roof flood light for physical damage, cracked lenses, or moisture intrusion, which frequently causes internal shorts.

2. 2

   Disconnect the harness at the light and inspect the pins for corrosion, melting, or debris.

3. 3

   Swap the front inner right light assembly with the front inner left light assembly. Clear codes and turn lights on. If the fault changes to the left side (RLC 521539.06), the light is internally shorted. If 521557.06 remains, the issue is in the wiring or RLC.

4. 4

   Using a multimeter, test the power circuit wire between the RLC and the light connector for continuity to ground. A continuity beep indicates the wire is chafed and touching the cab frame.

1. 1

   Power Down

   Turn off the tractor ignition and disconnect the negative battery cable to prevent electrical arcing during repair.

2. 2

   Access the Circuit

   Remove the necessary cab roof trim or bezel to access the front inner right work light and its pigtail connector.

3. 3

   Address the Fault

   If the light was faulty: Unbolt the old light assembly, mount the new replacement light, and plug it into the harness. If the wiring was shorted: Locate the chafed section of the harness (often where it routes through the roof frame). Repair the wire using a weatherproof butt connector and heat-shrink tubing, then wrap it in anti-chafe loom. If the RLC is faulty (rare, but possible if wiring and light test good): Access the Cab Roof Module, disconnect its main harness, and replace the module. (Note: A new RLC may require software calibration via John Deere Service Advisor).

4. 4

   Reassembly

   Reconnect the battery.

5. 5

   Verification

   Turn the ignition on, clear the stored fault codes via the tractor's CommandCenter display, and turn on the work lights. Verify that the lights function properly and the 521557.06 code does not return.