FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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H44 - Check HO2S Heater Relay Circuit For Short to Ground

- Key "OFF".

- Heated Oxygen Sensor (HO2S) heater relay disconnected.

- Breakout box installed, leave Powertrain Control Module (PCM) disconnected.

- Measure the resistance between test pin 14 and test pins 40, 46 and 60 at the breakout box.

- Is the resistance greater than 10,000 ohms?

Yes -- Go to H45

No -- Service short in harness. Remove breakout box. Reconnect all components. Rerun Quick Test.