Catalyst Monitor Active Airfuel Ratio Control Type

Vehicle Speed

Between 40 and 70 mph (64 and 113 km/h)

Idling v Ignition Switch ON


This test will not be completed if the vehicle is driven under adsolutely constant speed conditions such as with cruise control activated.


Warm up At least 10 minutes (Note: Even when vehicle stops during drive pattern, test can be resumed.)


(a) Preconditions

The monitor will not run unless:

(b) Drive Pattern

(1) Connect an intelligent tester or OBDII scan tool to the DLC3.

(2) Turn the ignition switch ON.

(3) Turn the tester or scan tool ON.

(5) Start the engine and warm it up.

(6) Drive the vehicle at between 40 mph and 70 mph (64 km/h and 113 km/h) for at least 10 minutes.

(c) Monitor Status

(1) Check the Readiness Monitor status displayed on the tester or scan tool.

(2) If the status does not switch to COMPL (complete), extend the driving time.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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