Massey Ferguson 05.X.81 – Suspension Module (Autotronic 5): Issue With Signal Voltage From Suspended Front Axle Position Sensor. (SUSPENSION)

The control module is receiving an irregular, out-of-range, or missing electrical signal from the front axle position sensor (X166). This can be caused by a sensor value that is too high, too low, or failing during the system's calibration process, causing the front axle suspension to become non-adjustable or default to a rigid state.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5400 Series
• 5600 Series
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613 iT4
• 5700 Series
• 6400 Series
• 6600 Series
• 6700 Series
• 6700 S
• 7400 Series
• 7600 Series
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7700 Series
• 8600 Series
• 8670
• 8690
• 8700 Series

1. 1

   Inspect the wiring harness leading to the X166 Suspended Front Axle Position Sensor for pinched wires, corrosion, or debris inside the connector

2. 2

   Test the sensor circuit for an open circuit, a short circuit to +12V, or a short circuit to earth (ground)

3. 3

   Verify the tractor's battery and alternator voltage (if the valve battery supply voltage drops below 9.5V, the suspension system will disable itself)

4. 4

   Check the +12V APC fuse box connection (circuit X167) which supplies power to the suspension components

1. 1

   Preparation

   Park the tractor on a level surface, engage the parking brake, and turn off the engine.

2. 2

   Locate the Sensor

   Locate the X166 position sensor on the front axle suspension linkage.

3. 3

   Remove the Faulty Sensor

   Disconnect the electrical harness from the sensor. Unbolt the sensor bracket/housing from the axle assembly.

4. 4

   Install the New Sensor

   Mount the replacement OEM sensor in the exact orientation as the old one. Torque the mounting hardware to the manufacturer's specifications and reconnect the electrical harness.

5. 5

   Perform Suspension Calibration

   After replacing the sensor, the Autotronic 5 module must relearn the axle's travel limits. Use the manual calibration method (hold the front axle suspension button on the console until it flashes, press and hold the 'up' button until the axle reaches its maximum top position, press and hold the 'down' button until it reaches the bottom stop, then release to center) or trigger the calibration sequence using a compatible diagnostic tool.

6. 6

   Clear Codes

   Delete the active fault codes from the Suspension Module.

7. 7

   Test Drive

   Operate the tractor on rough terrain for about 5 minutes to ensure the suspension adjusts properly and the fault code does not return.