John Deere 2370.03 – RLC / CLC / CAB: Right Turn Signal High Voltage

The controller is detecting higher-than-expected voltage on the right turn signal circuit, which typically points to a short circuit to a power source, a faulty bulb, or a failed flasher relay/module.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 250D
• 300D Series II
• 260E
• 310E
• 310SK
• 410K
• 524K
• 544K
• 624K
• 944K Hybrid
• 770G
• 770GP
• 772G
• 772GP
• 8245R
• 8270R
• 8295R
• 8320R
• 8335R
• 8345R
• 8370R
• 8400R
• 9470 STS
• 9570 STS
• 6M Series
• 6R Series

1. 1

   Inspect the right front (E36) and right rear (E38) turn signal bulbs for blown filaments or internal shorts

2. 2

   Visually inspect the right turn signal circuit wiring for exposed wires rubbing against the frame or other powered lines

3. 3

   Inspect harness connections at the turn signal housings, flasher relay, and cab/lighting controller for corrosion, bent pins, or moisture

4. 4

   Use a multimeter to test the right flasher circuit for continuity and verify it is not receiving unintended voltage when the switch is off

1. 1

   Disconnect Power

   Turn off the machine and disconnect the battery to prevent further electrical damage.

2. 2

   Bulb Replacement

   If the right turn signal bulbs are blackened, blown, or internally shorted, replace them first.

3. 3

   Harness Repair

   If the multimeter test reveals a short to power in the wiring harness, trace the wire from the affected light (front or rear) back to the controller. Splice and repair any damaged sections of the wire, and wrap it in protective loom.

4. 4

   Relay/Flasher Replacement

   If the wiring and bulbs are intact, the flasher relay or module may be internally shorted. Locate the flasher relay in the fuse/relay panel and replace it.

5. 5

   Module Testing

   If the code persists after replacing the bulbs, repairing the harness, and swapping the flasher relay, the RLC, CLC, or CAB module itself may have a failed internal driver. Replace the controller as a last resort.

6. 6

   Clear and Verify

   Reconnect the battery, clear the inactive fault codes via the monitor, and activate the right turn signal to verify the repair.