John Deere 523951.1 – SFA (Suspended Front Axle) Control Unit: SFA Not Reached The Required Position

This code indicates that the Suspended Front Axle (SFA) did not reach its expected or commanded position during operation or during a calibration routine. The position sensor failed to detect the required upward or downward movement within the expected timeframe (usually 10 seconds).

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6090MC
• 6090RC
• 6100MC
• 6100RC
• 6110MC
• 6110RC

1. 1

   Check the transmission/hydraulic fluid levels and ensure there are no leaks. Inspect the hydraulic pump and lines for proper operation.

2. 2

   Inspect the front suspension system for any mechanical obstructions, accumulated debris, or physical damage that might prevent the axle from moving up or down.

3. 3

   Test the SFA position sensor (right/left) to ensure it is receiving the correct power supply voltage and that the wiring harness is free of corrosion or disconnections.

4. 4

   Check the raise/lower command solenoids (Level 1 and Level 2 solenoid valves) for proper operation and ensure they are receiving the correct signals from the SFA module.

5. 5

   Ensure the tractor is in PARK. Check that the suspension cylinders are not fully extended. If they are fully extended, the SFA module will not detect movement and will fail the calibration.

1. 1

   Clear Obstructions

   Remove any debris or mechanical obstructions found around the front axle suspension.

2. 2

   Correct Fluid Levels

   Top up the hydraulic oil reservoir if the level is low.

3. 3

   Replace Defective Components

   If diagnostic tests isolate a failure, replace the faulty SFA position sensor, damaged wiring harness, or defective solenoid valve.

4. 4

   Prepare for Calibration

   If the suspension cylinders are fully extended, manually adjust them: with the engine OFF, disconnect the axle position feedback sensor link from the lower pivot pin. Push the link all the way up to its stop (tape it if necessary). Start the engine to allow the cylinders to retract, then reconnect the link.

5. 5

   Recalibrate the SFA

   Initiate the SFA calibration procedure via the tractor's CommandCenter display.

6. 6

   Verify Repair

   Allow the calibration to run. Successful calibration is confirmed when the display shows 'END' without throwing any active error codes.