P2222 Fault Code

NOx Sensor Heater Sense Circuit Range/Performance Bank 2

• What does that mean?
• Symptoms
• Causes
• Solutions

The P2222 fault code indicates a problem with the NOx sensor heater sense circuit range or performance specifically for Bank 2. This code is associated with the measurement of nitrogen oxides (NOx) emissions, which are critical for meeting environmental standards. The fault may arise when the heater in the NOx sensor fails to operate within the specified range or does not perform as expected.

Effective functioning of the sensor is crucial for the after-treatment system to reduce harmful emissions, and issues with the heater can lead to inaccurate sensor readings and poor vehicle performance.

What are the symptoms of the P2222 code?

When diagnosing a P2222 fault code, you may notice symptoms such as:

• Increased nitrogen oxide emissions, leading to potential emission test failures
• Poor engine performance, including rough idling or hesitation
• Check Engine Light illuminating on the dashboard
• Possible decrease in fuel efficiency
• The vehicle may enter limp mode to protect the engine and reduce emissions

What causes the P2222 code?

This fault code can result from several factors, including:

• A defective NOx sensor heater
• Poor wiring or connections leading to intermittent signals
• Malfunctioning Engine Control Unit (ECU)
• Issues with the vehicle's emissions system
• Contamination or damage to the NOx sensor
• Short circuits or open circuits in the sensor circuit

How to fix P2222?

To address a P2222 fault code, technicians typically recommend the following steps:

• Inspect the NOx sensor and its wiring harness for any signs of damage or corrosion
• Test the NOx sensor heater for proper functionality and replace if found defective
• Check for any fault codes or issues with the Engine Control Unit (ECU)
• Ensure all connections are secure and clean, and repair any wiring faults as needed
• Clear the fault codes and test drive the vehicle to ensure the issue is resolved.