Conditioning For Sensor Testing

HINT:

Intelligent tester only:

Malfunctioning areas can be identified by performing the A/F CONTROL function provided in the ACTIVE TEST. The A/F CONTROL function can help to determine whether the Air-Fuel Ratio (A/F) sensor, Heated Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the A/F CONTROL operation using an intelligent tester.

(1) Connect an intelligent tester to the DLC3.

(2) Start the engine and turn the tester ON.

(3) Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.

(4) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROL.

(5) Perform the A/F CONTROL operation with the engine in an idling condition (press the RIGHT or LEFT button to change the fuel injection volume).

(6) Monitor the voltage outputs of the A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S B2S2) displayed on the tester.

HINT:

• The A/F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection volume by 25 %.

• Each sensor reacts in accordance with increases and decreases in the fuel injection volume. Standard

Tester Display (Sensor)

Injection Volumes

Status

Voltages

AFS B1S1 or AFS B2S1 (A/F)

+25 %

Rich

Less than 3.0

AFS B1S1 or AFS B2S1 (A/F)

-12.5 %

Lean

More than 3.35

O2S B1S2 or O2S B2S2 (HO2)

+25 %

Rich

More than 0.55

O2S B1S2 or O2S B2S2 (HO2)

-12.5 %

Lean

Less than 0.4

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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