Conditions for Setting the DTC

Condition 1

• The ECM detects that the front HO2S is operating too rich while the rear is operating too lean and the ECM detects that the fuel trim is at minimum control.

  Or

• The rear fuel trim, long and short term, is less than a threshold.
• After the air flow coming into the engine accumulates to more than 200 grams and the above conditions are met, this DTC sets.

Condition 2

• The ECM detects that the rear HO2S is operating too lean while commanding a rich condition.
• After the air flow coming into the engine accumulates to more than 800 grams and the above condition is met, this DTC sets.