Massey Ferguson 05.03.81 – Suspension Module: Issue With Signal Voltage From Suspended Front Axle Position Sensor

The system is detecting that the voltage signal coming from the front axle position sensor (X166) is out of its expected range (either too high or too low).

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5400 Series
• 5425
• 5435
• 5445
• 5455
• 5460
• 5465
• 5470
• 5480
• 5600 Series
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5700 Series
• 6400 Series
• 6600 Series
• 6700 Series
• 7400 Series
• 7600 Series
• 7614 through 7626
• 7700 Series
• 8600 Series
• 8650
• 8660
• 8670
• 8680
• 8690
• 8700 Series

1. 1

   Inspect the wiring harness and connector leading to the X166 front axle position sensor for moisture intrusion, dust, and corrosion.

2. 2

   Use a multimeter to verify there is no open circuit, short circuit to ground (-), or short circuit to +12V in the sensor wiring harness.

3. 3

   Observe tractor symptoms such as erratic hitch movement, inability to maintain set suspension positions, or the suspension/hydraulics reverting to manual mode.

1. 1

   Preparation

   Park the tractor on level ground. If required by the specific model's service manual, relieve hydraulic pressure from the front suspension system before working near the axle.

2. 2

   Removal

   Locate the front axle position sensor (X166) on the front axle assembly. Carefully disconnect the electrical harness. Unbolt and remove the faulty sensor.

3. 3

   Installation

   Install the new sensor. Note: Handle with care as these sensors are precision electronic instruments.

4. 4

   Sealing

   Reconnect the wiring harness, ensuring the connection is perfectly clean and properly sealed to prevent future moisture intrusion.

5. 5

   Calibration

   After installation, you must perform a front axle suspension calibration. The suspension module needs to learn the new sensor's voltage values for the upper and lower physical limits of the axle. Failure to calibrate will result in subsequent calibration fault codes (such as FA135 or FA136).

6. 6

   Clear Codes

   Clear the 05.03.81 fault code from the system and test the suspension and steering to ensure smooth operation.