Diagnostic Aids

For any test that requires probing PCM or component harness connectors, use Connector Test Adapter Kit (J-35616-A). This will prevent damage to harness connector terminals. Check for the following conditions:

HO2S pigtail or harness may be mispositioned and contacting exhaust system. Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal-to-wire connection, corrosion or water intrusion.

An oxygen supply inside HO2S is necessary for proper operation. This supply of oxygen is provided through HO2S wiring harness. All HO2S wires and connections should be inspected for breaks or contamination. Repair as necessary.