2B06
Moderate2B06 — NOx Sensor: Linear Lambda Signal
Description
What the Code Means
Code 2B06 points to a fault in the linear lambda measurement of the nitrogen oxide (NOx) sensor. The NOx sensor measures nitrogen oxide concentration in the exhaust and simultaneously outputs a linear lambda signal that the control unit uses to correct fuel delivery.
The code is similar to 2AF2 but may refer to a different engine bank. The fault category is the EGR/DPF/SCR system, severity moderate.
Symptoms
Symptoms
- Check Engine light comes on;
- increased fuel consumption.
Causes and fixes
Diagnosis and Repair
Step 1. Check the Readings
Read and check the NOx sensor readings with INPA. Compare the actual lambda signal values against the expected ones — a mismatch points to a faulty sensor.
Step 2. Replace the Sensor
If the fault is confirmed, replace the NOx sensor.
Possible secondary damage
Secondary Problems
- Incorrect lambda readings can lead to improper fuel mixture formation, which affects engine operation and fuel consumption.