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HO2S Monitor Code

NOTE: Once test is started DO NOT turn ignition switch off. When negative battery cable is disconnected, all readiness codes are cleared.

Ensure ambient temperature is 20-95°F (-7-35°C).

  1. Connect scan tool to DLC.
  2. Start engine and hold at 3000 RPM with no load (in park or neutral) until radiator fan comes on.
  3. Let engine idle for 5 seconds.
  4. Drive vehicle at steady speed between 50 and 62 MPH for about two minutes
  5. With A/T in "D" position, M/T in 5th gear, decelerate from 62 MPH by completely releasing throttle for 5 seconds.
  6. Bring vehicle to a stop. Leave engine running at idle speed. If engine is stalls or is shut off during this part of procedure, repeat procedure starting in step  4.
  7. Readiness code should now be set. Use scan tool to check readiness code.
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