Massey Ferguson 05.X.84 – Suspension Module Dyna VT (SUSPENSION) / Autotronic 5: Issue With Signal Voltage From Suspended Front Axle Position Sensor During Calibration (SUSPENSION)

During the calibration routine for the suspended front axle, the electronic control unit is receiving an erratic, out-of-range, or implausible voltage signal from the front axle position sensor (X166 sensor). This prevents the tractor from successfully learning the upper and lower limits of the axle's suspension travel.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 6712 S
• 6713 S
• 6714 S
• 6715 S
• 6716 S
• 6718 S
• 7465-7499
• 7714-7726
• 8650-8690
• 8727-8740
• 5400 Series
• 5700 Series
• 6400 Series
• 6600 Series
• 7600 Series

1. 1

   Inspect the X166 sensor wiring harness and connector for moisture intrusion and corrosion from hydraulic fluid or road salt

2. 2

   Check for accompanying codes (e.g., FA133, FA221, FA134, FA222, FA135, FA224, FA136, FA225) that might pinpoint the electrical fault

3. 3

   Verify that the sensor's mechanical linkage to the axle is intact, not bent, and moves freely

1. 1

   Clean and Reseat

   Disconnect the X166 sensor, clean the contacts with electronic cleaner, ensure the weather seal is intact, and reconnect.

2. 2

   Replace the Sensor

   If the wiring is sound but the voltage signal remains erratic during calibration, the internal electronics of the sensor have likely failed and the sensor must be replaced.

3. 3

   Perform Front Axle Calibration

   After replacing the sensor or fixing the wiring, the suspension system must be recalibrated. Field Calibration Method: Start the tractor. Press and hold the front axle suspension button until it flashes, then release it. Press and hold the button again until the suspension reaches the absolute top of its travel, then release. Press the 'down/off' button until it reaches the absolute bottom, then release. The system will then center itself between the stops. Alternatively, refer to section 8.2.5 in the Massey Ferguson Technician Service Book for the OEM Manual Method.