John Deere 522451.02 – XSC (Steering System Control Unit) or SSU (Steering System Unit / AutoSystem SSU): Wheel Angle Sensor, Voltages in Channel 1 and Channel 2 Not in Correct Ratio

The Wheel Angle Sensor (WAS) on the front axle consists of two separate internal sensors (Channel 1 and Channel 2). For the system to function correctly, Sensor 2's signal voltage must be exactly half of Sensor 1's voltage (a 1:2 ratio). This code is triggered when the control module detects a deviation of 0.4 volts or more from this expected ratio. When this occurs, AutoTrac and automated steering functionalities are typically disabled.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6145J
• 6165J
• 6180J
• 6205J
• 6135M
• 6150M
• 6170M
• 6190M
• 6210M
• 7R Series
• 8235R
• 8245R
• 8260R
• 8285R
• 8310R
• 8320R
• 8335R
• 8360R
• 8400R
• 7030 Premium
• 8330

1. 1

   Jack up the front of the tractor and check for mechanical play in the steering ball joints and linkage, which can skew readings.

2. 2

   Use a diagnostic tool to monitor the live voltage levels of Channel 1 and Channel 2 to see if they are maintaining the required 1:2 ratio.

3. 3

   Perform a voltage drop test on the circuits from the sensor back to the XSC/SSU module (specification is typically 0.2 volts per connection).

4. 4

   Inspect the wiring harness and interconnects on the side of the tractor for poor factory crimps, corrosion, or loose pins that could cause resistance.

1. 1

   Repair Wiring

   If the voltage drop test reveals high resistance, locate the faulty connector or crimp. Cut out the bad connection and repair the harness using proper heat-shrinkable connectors to ensure a weather-tight, low-resistance joint.

2. 2

   Replace the Sensor

   If the wiring is intact and the sensor itself is failing to output the correct voltage ratio, the Wheel Angle Sensor must be replaced. Remove the sensor from the steering angle sensor shaft and install the new unit.

3. 3

   Update Software

   Check for and install any available updates for the XSC/SSU control software to address potential signal processing bugs.

4. 4

   Calibrate

   After replacing the sensor or repairing the wiring, clear the diagnostic trouble codes and perform a Wheel Angle Sensor calibration via the tractor's display or John Deere Service ADVISOR.