John Deere 84.09 – RPT: CAN BUS Message Fault - Wheel Speed Message Missing

The control module is not receiving the expected wheel speed or vehicle speed data from the transmission or wheel speed sensors due to an abnormal update rate or a loss of communication on the CAN bus.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 7610
• 7710
• 7810
• 8230T
• 8330T
• 8430T
• 9230
• 9330
• 9430
• 9530
• 9630

1. 1

   Check for accompanying codes (such as power supply or unswitched voltage codes like 000168.03/000168.04) that indicate the module lacks power.

2. 2

   Inspect the CAN Bus integrity by verifying the wiring harness between the wheel speed sensor, the transmission, and the RPT (or SSU) module for pinched wires, corrosion, or loose connector pins.

3. 3

   Visually inspect the wheel speed sensors for physical damage, accumulated debris, or mud that could block the sensor's magnetic pickup.

4. 4

   Verify the fuses powering the RPT/SSU modules (e.g., Fuse F23).

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery if you are repairing wiring.

2. 2

   Clean the Area

   Clear any dirt, debris, or mud from the wheel speed sensors and the RPT module connections.

3. 3

   Repair Wiring

   If the diagnostic checks revealed a broken or chafed wire on the CAN bus line leading to the RPT module, splice and seal the wire using an OEM-approved wiring repair kit, or replace the damaged harness section.

4. 4

   Replace the Sensor

   If the wiring is intact but the sensor fails continuity/resistance tests, remove the faulty wheel speed sensor and install a new one.

5. 5

   Reassemble and Clear Codes

   Reconnect the battery, turn the key to the ON position, and use a diagnostic scanner (or the CommandCenter display) to clear the 000084.09 fault code.

6. 6

   Test Drive

   Restart the vehicle and drive it forward to verify that the wheel speed message is successfully broadcasting to the RPT module and the code does not return.