John Deere 2390.06 – RLC (Roof Lighting Control Unit): License Plate Light Current High (Eur Only) / License Plate Light, Current Too High

This code indicates that the electrical current draw in the license plate light circuit is exceeding the expected threshold. This is typically caused by a short circuit to ground, a damaged wiring harness, or a faulty/incorrect bulb.

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

1. 1

   Cycle the key switch or tractor power to see if the intermittent code clears by rebooting the RLC module.

2. 2

   Check the license plate light bulb to ensure it is not burnt out, internally shorted, or replaced with an incorrect wattage bulb that draws too much amperage.

3. 3

   Inspect the license plate light wiring harness for pinched wires, exposed copper, or chafing against the tractor frame (which would cause a short to ground).

4. 4

   Perform the RLC—License Plate Light Circuit Test as outlined in the John Deere TM146419 / TM119019 manuals to isolate whether the short is in the harness or the lamp assembly itself.

1. 1

   Disconnect Power

   Turn off the tractor and remove the key to ensure no power is flowing to the RLC module.

2. 2

   Access the Lamp

   Locate the license plate light assembly at the rear of the tractor.

3. 3

   Inspect and Clean

   Unplug the lamp from the wiring harness. Thoroughly clean the connection points, as dirt and corrosion in this area are common causes of electrical faults.

4. 4

   Replace Faulty Component

   If the wiring harness is damaged or shorted, splice in a repair or replace the harness section. If the lamp assembly is internally shorted, remove the mounting screws and install a direct replacement lamp.

5. 5

   Apply Dielectric Grease

   Apply dielectric grease generously to the electrical connector before plugging it back in. This area is highly susceptible to road spray, chemicals, and moisture.

6. 6

   Test

   Turn the tractor on, activate the lighting system, and verify that the license plate light illuminates and the 002390.06 code clears from the CommandCenter™ display.