Component Inspection
■ Check HO2S
- IG "OFF". Disconnect HO2S connector.
- Check that the HO2S is securely installed.
- Check the HO2S for contamination or damage, water intrusion in connector, incorrect fuel pressure, VAC leaks.
- Is the sensor normal?
YES
- Go to "Check the Signal waveform of HO2S" as below.
NO
- Substitute with a known - good HO2S and check for proper operation. If the problem is corrected, go to "VERIFICATION OF VEHICLE REPAIR " procedure.
■ Check the Signal waveform of HO2S
- IG "OFF". Connect HO2S connector.
- Connect probe to HO2S to measure signal waveform using oscilloscope function. Start engine.
- After warming-up, monitor signal waveform of HO2S with GDS.
- Is the sensor switching properly?
YES
- Substitute with a known - good PCM and check for proper operation. If the problem is corrected, replace PCM and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
- Substitute with a known - good HO2S and check for proper operation. If the problem is corrected, go to "VERIFICATION OF VEHICLE REPAIR " procedure.