H23 - Check of HO2S Circuit Wiring With PCM Connected

- Key Off.

- PCM connected.

- Suspect HO2S disconnected.

- Jumper HO2S Signal to VPWR at the HO2S harness connector.

- Scan Tool connected.

- Key On, Engine Off.

- Access the correct HO2S PID.

NOTE: (HO2S displayed as 02S on Scan Tool.)

- Is the voltage greater than 3.50 volts?

YES -- HO2S signal circuit is not faulty. REPLACE HO2S, change oil/filter, COMPLETE PCM reset to clear DTCs. COMPLETE a HO2S monitor drive cycle.

NO -- Go to H24. H24 - Check Resistance of HO2S Signal Circuit