Perform Active Test Using Intelligent Tester Injection Volume

(a) Connect an intelligent tester to the DLC3.

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

(d) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / INJ VOL.

(e) Change the fuel injection volume using the tester, monitoring the voltage output of Air-Fuel Ratio (A/F) and HO2 sensors displayed on the tester.

HINT:

• 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 or AFS B2S1, and the HO2 sensor is displayed as O2S B1S2 or O2S B2S2, on intelligent testers.

Result

Tester Display (Sensor)

Voltage Variations

Proceed To

AFS B1S1 (A/F) AFS B2S1 (A/F)

Alternates between more and less than 3.3 V

OK

AFS B1S1 (A/F) AFS B2S1 (A/F)

Remains at more than 3.3 V

NG

AFS B1S1 (A/F) AFS B2S1 (A/F)

Remains at less than 3.3 V

A normal HO2 sensor voltage (O2S B1S2 or O2S B2S2) 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.

REPLACE AIR FUEL RATIO SENSOR

CHECK AND REPAIR EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO (INJECTOR, FUEL PRESSURE, GAS LEAKAGE FROM EXHAUST SYSTEM, ETC.)

CHECK EXHAUST GAS LEAKAGE

No gas leakage.

REPAIR OR REPLACE EXHAUST GAS LEAKAGE POINT

INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

(a) Disconnect the H3 or H4 HO2 sensor connector.

(b) Measure the resistance between the terminals of the HO2 sensor connector.

Standard Resistance

Tester Connections

Specified Conditions

HT1B or HT2B (1) - +B (2)

11 to 16 n at 20°C (68°F)

HT1B or HT2B (1) - E2 (4)

10 kn or higher

(c) Reconnect the HO2 sensor connector.

REPLACE HEATED OXYGEN SENSOR

INSPECT EFI RELAY

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

Don't pay hundreds of dollars to find out what is wrong with your car. This book is dedicated to helping the do it yourself home and independent technician understand and use OBD-II technology to diagnose and repair their own vehicles.

Get My Free Ebook


Post a comment