• Change the fuel injection volume within the range of -12 % and +12 %. The injection volume can be changed in 1 % graduations within the range.

• The A/F sensor is displayed as AFS B1S1, and the HO2 sensor is displayed as O2S B1S2, on intelligent testers. Result

Display (DTC Output)

Voltage Variations

Proceed To

AFS B1S1 (A/F)

Alternates between more and less than 3.3 V


AFS B1S1 (A/F)

Remains at more than 3.3 V


AFS B1S1 (A/F)

Remains at less than 3.3 V

A normal HO2 sensor voltage (O2S B1S2) reacts in accordance with increases and decreases in fuel injection volumes. When the A/F sensor voltage remains at either less or more than 3.3 V despite the HO2 sensor indicating a normal reaction, the A/F sensor is malfunctioning.

Injection Volume

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