H86 - Check Continuity of HO2S and HO2S Ground Circuits

- Key Off.

- Breakout box installed, PCM disconnected.

- Disconnect suspect HO2S from harness.

- Measure the resistance between HO2S Signal Test Pin at the breakout box and the HO2S harness connector. Record readings.

- Measure resistance between SIG RTN Test Pin at the breakout box and HO2S SIG RTN harness connector. Record readings.

- HO2S-12 SIG = Test Pin 35
- HO2S-22 SIG = Test Pin 61
- HO2S SIG RTN = Test Pin 91

- Is the resistance reading less than 5.0 ohms?

YES -- If sent here from Pinpoint Test Step HF2, HO2S testing is complete. RETURN to HF3 for additional testing. HF3 - Check For ECT Sensor DTCs

Otherwise: REPLACE PCM. REMOVE breakout box. RECONNECT all components. COMPLETE a HO2S Monitor Drive Cycle. Monitors, Trips, Drive Cycles and Readiness Codes

NO -- REPAIR open circuit in harness. REMOVE breakout box. RECONNECT all components. COMPLETE a HO2S Monitor Drive Cycle. Monitors, Trips, Drive Cycles and Readiness Codes