John Deere 84.09 – PTF, SSU, SST, or CCU: CAN BUS Message Fault

Wheel Speed Message is Missing or the Vehicle Speed is Invalid/Missing. The control module is failing to receive the expected wheel speed data over the CAN bus communication network.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110M through 6195M
• 6110R through 6215R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 7810
• 8230T
• 8330T
• 8430T
• 9230
• 9330
• 9430
• 9530
• 9630
• 9560 STS
• 9660 STS
• 9760 STS
• 9860 STS

1. 1

   Restart the vehicle to see if the code clears, as temporary communication glitches on the CAN bus can trigger this code

2. 2

   Check for voltage issues by visually inspecting the batteries and alternator for signs of damage, loose connections, or accumulated debris

3. 3

   Check for companion codes like 168.03 or 168.04 (Unswitched Supply Voltage Problem). If present, check the module's supply fuses (e.g., Fuse F23 or F35) before assuming the speed sensor is bad

4. 4

   Visually inspect the wiring harness between the wheel speed sensor, the transmission controller, and the PTF/SSU for chafing, breaks, or severe corrosion

1. 1

   Power Down

   Turn off the machine and disconnect the battery to prevent electrical spikes during testing.

2. 2

   Locate the Sensor

   Locate the wheel speed sensor (location varies by model, typically mounted on the transmission housing, differential case, or wheel hub).

3. 3

   Test the Sensor

   Disconnect the sensor harness. Using a multimeter, test the wheel speed sensor for proper resistance and signal output according to the specific model's technical manual specifications.

4. 4

   Test the CAN Bus

   Check the CAN bus terminating resistors (typically 60 ohms across the network) and verify continuity between the PTF/SSU module connector and the speed sensor/transmission controller connector.

5. 5

   Replace/Repair

   If the sensor fails the resistance/signal test, replace it. If the sensor is good but continuity is broken, repair the damaged section of the CAN bus wiring harness.

6. 6

   Clear and Verify

   Reconnect the battery, clear the diagnostic trouble codes via the CommandCenter or diagnostic tool, and test drive the machine to verify the wheel speed message is restored and the code does not return.