Massey Ferguson R22 – HITCH: Rear Hitch Position Sensor Signal Voltage Issue

The electronic signal voltage being sent from the rear hitch position sensor (lift arm sensor) to the controller is outside of the expected operating parameters. This is typically caused by an open circuit, a short to ground, a short to power, moisture intrusion in the connector, or a complete internal failure of the sensor potentiometer.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• 5708
• 5709
• 5710SL
• 5711SL
• 5712SL
• 5713SL
• 7714
• 7715
• 7716
• 7718
• 7719
• 7720
• 7722
• 7724
• 6600 Series
• 6700 Series
• 7600 Series
• 8600 Series

1. 1

   Inspect the sensor housing and wiring harness at the rear rockshaft/lift arms for physical damage from debris or implement interference.

2. 2

   Disconnect the sensor and check for moisture intrusion, dirt, or corrosion on the pins.

3. 3

   Verify that the sensor is receiving the correct reference voltage (typically 5V) and has a solid ground from the HITCH controller.

4. 4

   Check the continuity of the signal wire from the sensor connector back to the HITCH ECU to rule out a broken wire or chafed harness shorting to the tractor chassis.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery to prevent electrical spikes to the HITCH controller.

2. 2

   Locate Sensor

   Locate the rear hitch position sensor mounted on the rear lift arm/rockshaft assembly.

3. 3

   Removal

   Carefully unplug the wiring harness connector. Remove the retaining hardware holding the sensor linkage and housing in place.

4. 4

   Installation

   Mount the new position sensor in the exact orientation as the old one. Reattach the mechanical linkage.

5. 5

   Reconnect

   Apply a small amount of dielectric grease to the connector seal to prevent future moisture intrusion, then plug the harness back in.

6. 6

   Calibration

   Reconnect the battery. You must perform a hitch calibration procedure using the tractor's terminal or dealer diagnostic software. The HITCH controller needs to learn the new sensor's minimum and maximum voltage values corresponding to the lowest and highest physical lift arm positions.