J25 - Check Left/Front Heated Oxygen Sensor or Short to Power
Heated Oxygen Sensor Connector View:
NOTE: Due to the internal circuitry of the Powertrain Control Module (PCM), a left/front Heated Oxygen Sensor (HO2S) signal short to power could produce a Diagnostic Trouble Code (DTC) 542 or 543.
- Key "OFF".
- Disconnect left or front HO2S sensor.
- Measure resistance between HO2S signal pin and KEY POWER pin at the HO2S sensor connector.
- Is resistance greater than 10,000 ohms?
Yes -- Go to J26. J26 - Check HO2S Circuit For Short to Power
No -- Replace HO2S. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)
Clear Keep Alive Memory. Clearing Keep Alive Memory (KAM) and Relearn Procedure