Kubota P2200 – Engine Control Module (ECM) / Engine ECU: NOx Sensor Circuit Bank 1 Sensor 1

Indicates that the engine's computer has detected a malfunction, open circuit, or loss of communication in the electrical circuit of the upstream Nitrogen Oxide (NOx) sensor.

• M7 series tractors
• M7-131P
• V3800-TIE5
• WG1605

1. 1

   Connect a diagnostic scan tool to confirm P2200 is active. Check for related codes (such as P220E for the heater control circuit).

2. 2

   Inspect the NOx sensor, its control module box, and the wiring harness. Look for melted wires from exhaust heat, chafing, broken insulation, or water ingress in the connector.

3. 3

   Backprobe the connector with the key in the ON position. Verify that the ECM is supplying the correct reference voltage (typically ~5V) and battery voltage to the heater supply lead. Check for proper ground continuity.

4. 4

   Check for heavy soot/carbon buildup that might be clogging the sensor element, and ensure there are no exhaust leaks upstream of the sensor that could skew readings.

1. 1

   Prep the Machine

   Turn the ignition key to the OFF position and disconnect the battery to prevent electrical shorts.

2. 2

   Locate the Sensor

   Find the Bank 1 Sensor 1 NOx sensor. It is mounted on the exhaust pipe prior to the SCR catalyst.

3. 3

   Disconnect Wiring

   Unplug the electrical connector linking the NOx sensor's control module to the main engine harness.

4. 4

   Remove the Sensor

   Carefully unscrew the NOx sensor from the exhaust bung. Note: These sensors frequently seize in the exhaust pipe due to extreme heat cycles. Use penetrating oil if necessary. If using a torch to break it loose, do not apply direct flames to the sensor body, as this will destroy the internal electronics.

5. 5

   Install the New Part

   Thread the new NOx sensor into the exhaust pipe and tighten it to the manufacturer's specified torque.

6. 6

   Route the Harness

   Securely route the new sensor's wiring harness away from direct exhaust heat and reconnect the electrical plug.

7. 7

   Clear Codes and Test

   Reconnect the battery, turn the ignition ON, and use your scan tool to clear the P2200 code. Start the engine and perform a test drive to bring the exhaust up to operating temperature (above ~600°F, the threshold where the NOx sensor activates) to confirm the code does not return.