John Deere 84.19 – Front Chassis Module (SFA): Wheel Speed Sensor Missing On CAN BUS

A control unit on the machine's CAN network transmits a status indicating that the wheel speed data is either missing, invalid, or unavailable. This is caused by an incorrect configuration of the wheel speed sensor in the controller or a physical circuit problem (open or short) at the wheel speed sensor itself.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6250R
• 8225R
• 8245R
• 8270R
• 8295R
• 8320R
• 8335R
• 8345R
• 8370R
• 8400R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 6230
• 6330
• 6430
• 5080R
• 5090R
• 5100R

1. 1

   Check for Accompanying Codes: Look for direct circuit fault codes like EPC 000084.14 or BCU 000084.02, which specifically indicate that the B09/B35 wheel speed sensor has an open circuit, invalid signal, or is failing to register speed when the clutch is released.

2. 2

   Verify Configuration: If a controller was recently replaced or reprogrammed, verify that the wheel speed sensor configuration (e.g., BCU Address 30) is correctly enabled in the software.

3. 3

   Inspect the Sensor and Harness: Locate the wheel speed sensor (B09/B35) on the transmission or axle housing. Inspect the 2-pin connector and wiring harness for physical damage, corrosion, or an open circuit.

4. 4

   Check CAN BUS Integrity: Since the SFA module is complaining about a missing message, ensure the CAN BUS wiring between the main Basic Control Unit (BCU) and the SFA module is intact.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery ground to ensure safety while working on the electrical system.

2. 2

   Locate the Sensor

   Find the magnetic pickup wheel speed sensor (B09/B35) on the transmission housing or wheel hub.

3. 3

   Test the Circuit

   Disconnect the sensor. Use a multimeter to check for continuity in the wiring harness back to the BCU/EPC. If the wiring is broken or shorted to a supply lead, repair the harness.

4. 4

   Replace the Sensor

   If the wiring is intact and the configuration is correct, the sensor itself has likely failed internally. Remove the retaining bolt, pull the old sensor out, and install the new OEM wheel speed sensor.

5. 5

   Re-calibrate / Clear Codes

   Reconnect the battery, turn the ignition on, and clear the stored fault codes. Test drive the tractor to ensure the speedometer registers ground speed and the SFA 000084.19 code does not return.