Circuit Description

The Heated Oxygen Sensor 2 (HO2S 2) located rear of catalytic converter produces an output signal relative to oxygen storage capacity of catalytic converter. HO2S 2 signal is less active than signal produced by front Oxygen Sensor 1 (O2S 1).

Conditions for setting this DTC are as follows:

• Engine coolant temperature is less than 104°F (40°C).
• Intake air temperature is less than 104°F (40°C).
• TP sensor angle is greater than 18 percent for greater than 5 seconds.
• Temperature difference between ECT sensor and IAT sensor is less than 45°F (7°C).
• HO2S 2 voltage changes less than 148 mV in 100-190 seconds.