W/Harness Inspection

Terminal and Connector Inspection

1. Ignition "ON" & Engine "OFF"
2. Monitor the O2 SNSR VOL.-B1/S2 parameter on the Scantool data list while wiggling the wiring harness and related connectors. Refer to "Signal Waveform & Data" in the "General Information" procedure.
3. The value should remain more or less unchanged. If not, check for the following conditions:
-Check for corrosion on terminals
-Check for terminal tension (at the HO2S and at the ECM)
-Check for damaged wiring
-Check the HO2S ground circuit for a good connection
-Check the 10A SNSR fuse
-Check front and rear HO2S for connections being reversed.
4. Was a problem found in any of the above areas?
YES
1) Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
1) Go to next step "Component Inspection" procedure.