John Deere 523908.19 – RPT (Rear PTO control software): Issue With External PTO Switch / Remote Control Switch for Rear PTO, Malfunction

The Operator Interface Control (OIC) or Armrest Interface Control (AIC) software cannot determine the values of the remote control switch for the rear PTO (the external fender switches). Because it cannot read the switch state, the system transmits a replacement value over the CAN bus, which generates this fault code. The functionality of the rear PTO is significantly limited or entirely non-functional for safety reasons.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R

1. 1

   Check for other OIC or BCU error codes (e.g., 523758.11 or 523759.11) to determine exactly which side is causing the issue.

2. 2

   Inspect the wiring harness and connectors leading to the external fender PTO switches for signs of an open circuit, short to ground, corrosion, or physical damage.

3. 3

   Test the remote control switches (Left: S44, Right: S121) for proper operation and continuity using a multimeter or diagnostic tools.

4. 4

   Verify CAN bus communication to ensure all messages from the OIC control software are being correctly transmitted and received by the RPT control software.

1. 1

   Identify malfunctioning switch

   Identify which external PTO switch (left or right rear fender) is malfunctioning based on secondary fault codes.

2. 2

   Access switch panel

   Access the rear fender inner PTO switch panel.

3. 3

   Inspect and clean wiring harness

   Disconnect the wiring harness from the affected PTO switch and inspect the pins for corrosion, moisture, or pushed-out terminals. Clean or repair the connector if necessary.

4. 4

   Remove defective switch

   If the wiring is intact but the switch failed the diagnostic continuity test, remove the defective switch from the fender panel.

5. 5

   Install new switch

   Install the new OEM replacement switch and reconnect the wiring harness.

6. 6

   Clear fault codes

   Clear the fault codes using a diagnostic tool.

7. 7

   Test PTO engagement

   Test the external PTO engagement to ensure full functionality has returned.

8. 8

   Update control software

   Ensure that both the OIC and RPT control software are updated to the latest versions to prevent communication glitches.