Downstream O2 Monitor

2000 Plymouth Breeze 2.0 C, Standard, A578SECTION Downstream O2 Monitor

Perform the following:

  • Ensure engine is at normal operating temperature, above 170°F.
  • Decel Fuel Shut-off is Active.
  • Minimum Engine RPM = 1600 RPM.
  • Upstream O2S is less than .471 volts.
The PCM begins the Downstream O2S rationality test. The PCM looks at the Downstream O2S volts for 5 seconds, if less than .295 volts, the test passes. If the Downstream O2S is greater than .295 volts, the test increments a count of 1 and the test is done again. A count of 3 will set a DTC and store Freeze Frame Data.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.