John Deere 002238.09 – RPT: CAN Bus Communication Issue With RPT

The system has detected a communication failure on the Controller Area Network (CAN) bus, specifically a loss of messaging between a primary control module and the Rear PTO Control Unit (RPT). The .09 Failure Mode Identifier (FMI) signifies an abnormal update rate, meaning expected messages are not being received at the correct interval or at all. This communication link failure may affect the operation of the PTO and related systems.

• 6M Series
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• R-series
• 6R Series
• 7M Series
• 7R Series
• 8R Series
• 9R Series
• 5 Series
• 6300 Series

1. 1

   Cycle the tractor's main power switch to see if communication re-establishes

2. 2

   Check for other fault codes across different modules, which could indicate a wider network problem rather than a single faulty component

3. 3

   Visually inspect the wiring harness and connectors associated with the RPT module for chafing, pinching, or corrosion

4. 4

   Perform a CAN Bus resistance check with power off at the 9-pin diagnostic connector (Pin C to Pin D). Expected: ~60 Ohms. 120 Ohms indicates an open circuit or missing terminating resistor; significantly less indicates a short

5. 5

   Perform a voltage check with power on (engine off). CAN High (Pin C) to ground should be 2.5-3.0V; CAN Low (Pin D) to ground should be 2.0-2.5V

1. 1

   Isolate the fault

   If CAN bus resistance is incorrect, unplug modules one at a time and re-measure. The disconnected component or its wiring is the source when resistance returns to normal (e.g., 120 Ohms drops to 60 Ohms).

2. 2

   Clean and secure connections

   If visual inspection reveals corrosion, clean any corroded pins and sockets thoroughly. Apply dielectric grease to protect against moisture and ensure a secure connection.

3. 3

   Repair harness damage

   Repair or replace damaged wiring sections. Ensure all repairs maintain the twisted-pair configuration of the CAN bus wires to prevent electrical interference.

4. 4

   Replace faulty module

   If diagnostics confirm the RPT module is causing incorrect resistance or voltage readings and the wiring is good, replace the RPT module.