Technical Definition:

O2 Circuit No Activity Detected (Bank 1, Sensor 3)

Technical Description:

The catalytic converter is used to control emissions. The o2 sensor on Bank 1, position 3 is aft of the converter and monitors the catalyst efficiency. The PCM (Powertrain Control Module) does this by comparing the post-cat o2 sensor to the pre-cat o2 sensors.

Possible Causes:

• Bad Bank 1, position 3, o2 sensor
• Wiring problem, melted harness, broken connectors, etc.
• Bad PCM

Possible Symptoms:

• MIL (Malfunction Indicator Lamp) on
• May idle or drive poorly
• Fuel economy may decrease

O2 Sensor Circuit No Activity Detected Bank 1 Sensor 3

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty Heated Oxygen Sensor Bank 1 Sensor 3
– Heated Oxygen Sensor Bank 1 Sensor 3 harness is open or shorted
– Heated Oxygen Sensor Bank 1 Sensor 3 circuit poor electrical connection

Specific Makes:

– High Fuel Consumption
– Excessive Smoke from Exhaust