John Deere 523908.31 – RPT (Rear PTO Control Module) or BCU (Basic Control Unit): Issue With External PTO Switch. Check Other Error Codes

The control software detects an open circuit in the wiring for the external remote control switch for the rear PTO, which significantly limits or disables rear PTO functionality as a safety precaution.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5080R
• 5090R
• 5100R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC

1. 1

   Check for Priority Codes: Check the system for any active OIC (Operator Interface Control) diagnostic trouble codes, which take priority over RPT codes.

2. 2

   Inspect the Circuit: Visually inspect the wiring and connections leading to the external fender-mounted PTO switch for signs of an open circuit, such as severed wires, corrosion inside the connector, or loose pins.

3. 3

   Test the Switch: Use a multimeter or John Deere diagnostic tools to test the remote control switch for proper continuity and operation when pressed.

4. 4

   Verify CAN Bus Communication: Ensure that CAN messages from the OIC control software are being correctly transmitted and received by the RPT control software.

1. 1

   Power Down

   Turn off the tractor, remove the key, and ensure the PTO is fully disengaged.

2. 2

   Access the Switch

   Locate the external rear PTO remote control switch on the left or right rear fender.

3. 3

   Disconnect the Harness

   Unplug the electrical harness connector from the back of the switch. Clean the connector with contact cleaner if dirt or corrosion is present.

4. 4

   Repair Wiring

   If the diagnostic checks revealed an open circuit in the harness, repair or replace the damaged wires/connectors.

5. 5

   Replace the Switch

   If the wiring is intact but the switch failed the continuity test, remove the mounting hardware or retaining clips securing the switch to the fender. Pull the old switch out and snap/bolt the new OEM switch into place.

6. 6

   Reconnect and Reassemble

   Plug the electrical harness back into the new switch.

7. 7

   Software Update

   Ensure that both the OIC and RPT control software are updated to the latest versions, as John Deere occasionally releases patches that address communication issues between these modules.

8. 8

   Clear and Test

   Clear the 523908.31 fault code using a diagnostic tool. Start the tractor and test the external PTO switch to verify the rear PTO engages and disengages correctly.