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H91 - Continuous Monitor DTM Test Drive Check



- Remain in Engine Running Continuous Monitor test mode.

- Test drive vehicle at 55 mph with minimum road load for five miles.

- Continue to drive on a rough road at 55 mph for five miles.

- If possible drive vehicle through a pool of water on the road to shower the Heated Oxygen Sensor (HO2S) and/or connector.

- Is a fault indicated?

Yes -- Isolate fault and service as necessary. Remove breakout box. Clear continuous memory code. Clearing Diagnostic Trouble Codes

Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Exit Engine Running Continuous Monitor test mode. Go to H92. H92 - Check HO2S Switching