Component Inspection

Component Inspection

1. 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.




(4) Is the sensor switching properly?
YES
- Check HO2S for poor connection/installation or damage.
If O.K., Substitute with a known-good ECM and check for proper operation.
If the problem is corrected, replace ECM 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.

CAUTION:
There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by ECM. Before or after testing ECM on the vehicle, use this function to reuse the ECM on the others