Massey Ferguson 05.01.81 – Suspension Module: Issue With Signal Voltage From Suspended Front Axle Position Sensor

The control module is receiving an irregular, out-of-range, or missing electrical voltage signal from the position sensor (X166). This sensor is responsible for monitoring the height and travel of the suspended front axle.

• 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
• 5700 Series
• 6400 Series
• 6600 Series
• 6700 Series
• 7400 Series
• 7600 Series
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7700 Series
• 8600 Series
• 8650
• 8660
• 8670
• 8680
• 8690
• 8700 Series

1. 1

   Use a diagnostic tool to read the live voltage of sensor X166 to determine if the sensor value is reading too high (short to +12V) or too low (short to ground/open circuit).

2. 2

   Inspect the wiring harness and connectors leading to the front axle position sensor for physical damage, corrosion, or moisture ingress.

3. 3

   Inspect the physical mounting of the sensor on the front axle linkage to ensure it hasn't been damaged by debris or knocked out of alignment.

4. 4

   Attempt a front axle calibration procedure, as the issue can sometimes stem from corrupted calibration values.

1. 1

   Safely park the tractor on level ground.

   If you need to work directly under the suspension components, properly support the front chassis to prevent the axle from dropping unexpectedly.

2. 2

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

3. 3

   Disconnect the electrical connector.

   Clean the contacts with electrical contact cleaner and check for broken pins.

4. 4

   Remove the mounting hardware securing the sensor to the axle.

   Perform this step if the wiring is intact but the sensor voltage remains out of specification.

5. 5

   Install the new position sensor and reconnect the wiring harness.

6. 6

   Perform the front axle suspension calibration procedure using the tractor's diagnostic interface (or dealer tool).

   This teaches the Suspension Module the new sensor's minimum and maximum travel limits.

7. 7

   Clear the 05.01.81 fault code and test drive the tractor.

   Ensure the suspension operates smoothly and the code does not return.