John Deere 523908.14 – BCU (Basic Control Unit) or RPT (Rear PTO Control Unit): Rear External PTO Switch Is On / INFORMATION FOR OPERATOR: Remote Control Switch for Rear PTO is Activated

This is an informational diagnostic trouble code (DTC) generated when the remote control switch for the rear PTO (located on the rear fender) is turned on or activated. It indicates that the rear PTO can now be engaged via the external fender switch. It only becomes a fault if the switch is stuck or activating without operator input.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5075M
• 5085M
• 5100M
• 5115M
• 6230
• 6330
• 6430
• 7430
• 7530 Premium

1. 1

   Verify Operator Intent: Confirm whether the operator intentionally pressed the rear fender PTO switch. If they did, the code is operating exactly as designed and no repair is needed.

2. 2

   Visual Inspection: If the code is active without operator input, inspect the external fender PTO switches (left and right sides) for physical damage, heavy dirt, or debris that might be wedging the button in the 'pressed' position.

3. 3

   Electrical Testing: Disconnect the fender switch and use a multimeter to test for continuity. Verify that the switch is not internally shorted or stuck in the closed position.

4. 4

   Harness Check: Inspect the wiring harness leading from the fender switch to the BCU/RPT for chafing, moisture ingress, or shorts to power/ground.

1. 1

   Clean the Switch

   If the switch is physically stuck due to mud or debris, thoroughly clean the fender switch housing and verify if the button springs back to its neutral position.

2. 2

   Replace Faulty Switch

   If the switch fails the continuity test (remains closed when not pressed) or is physically broken, remove the retaining bezel/screws on the rear fender, disconnect the electrical pigtail, and install a new OEM switch.

3. 3

   Repair Wiring

   If the switch tests fine but the code persists, trace the wiring harness back to the BCU. Repair any damaged wires or clean corroded connector pins.

4. 4

   Clear Codes

   Turn the tractor key cycle off and back on. Clear the stored codes via the cab display and verify that 523908.14 does not return unless the fender switch is intentionally pressed.