Component Inspection

Engine

Engine Control - P0140 O2 Sensor Circuit No Activity Detected (Bank 1 / Sensor 2) Component Inspection

Component Inspection

Check the Signal waveform of HO2S
1. IG "OFF" and connect HO2S connector.
2. Engine start.
3. After warming-up, monitor signal waveform of HO2S with scantool.












Fig.1) Normal waveforms of front HO2S (the upper) and rear HO2S. (the lower) (chassis ground used)
Fig.2) Normal waveforms of front HO2S (the upper) and rear HO2S. (the lower) (sensor ground used)
4. Is the sensor switching properly?





Check HO2S
1. IG "OFF" and disconnect HO2S connector.
2. Check that the HO2S is securely installed.
3. Check the HO2S for contamination or damage.
4. Is the sensor normal?