John Deere 520870.13 – SFA (Suspended Front Axle Control Unit): Suspended front-wheel drive axle, Malfunction during calibration

The control unit failed to successfully calibrate the front axle suspension system, typically due to invalid data, a loss of configuration memory, or an out-of-range reading from the front axle position sensor during the calibration routine.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 7630
• 7720
• 7730
• 7820
• 7830
• 7920
• 7930
• 7200R
• 7215R
• 7230R
• 8130
• 8230
• 8330
• 8430
• 8530
• 8225R
• 8245R
• 8270R
• 8295R
• 8320R
• 8335R
• 8345R
• 8370R
• 8400R

1. 1

   Inspect the front axle position sensor and its mechanical linkage for physical damage, bent rods, or accumulated mud/debris that could restrict its movement.

2. 2

   Inspect the wiring harness and connectors leading to the position sensor for signs of chafing, corrosion, or disconnection.

3. 3

   Verify that the sensor is receiving the correct reference supply voltage from the SFA control unit (typically 5.0 Volts).

4. 4

   Check the SFA system fuses (e.g., F6, F13, F30, or F35 depending on your specific transmission and model) to ensure the module is fully powered.

5. 5

   Restart the vehicle and operate it on rough terrain for 5 minutes to see if the suspension responds to commands and if the code transitions from active to stored.

1. 1

   Clean the Area

   Remove any debris and thoroughly clean the Independent Link Suspension (ILS) or Triple-Link Suspension (TLS) manifold and the sensor linkage area.

2. 2

   Repair Wiring

   If any wiring faults or connector pin issues were found during diagnostics, repair or replace the damaged harness sections.

3. 3

   Replace Sensor (If Defective)

   If the sensor linkage is broken or the sensor fails to return a smooth, linear voltage sweep during testing, replace the front axle position sensor.

4. 4

   Perform SFA Calibration

   Re-calibrate the SFA system via the tractor's CommandCenter display (following the on-screen prompts for suspension calibration) or by using the John Deere Service ADVISOR diagnostic tool.

5. 5

   Clear Codes

   Cycle the ignition key (turn off, wait, and turn back on) to verify the configuration data is saved and the 520870.13 code is cleared.