Toyota FJ Cruiser (GSJ 10, 15 series). Instruction — part 51

1GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM

ES–159

ES

TYPICAL ENABLING CONDITIONS

Fuel-trim:

TYPICAL MALFUNCTION THRESHOLDS

Fuel-trim:

WIRING DIAGRAM

Refer to DTC P2195 (See page

ES-312

).

INSPECTION PROCEDURE

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 %.

Monitor runs whenever following DTCs not present

P0010, P0020 (OCV Bank 1, 2)
P0011 (VVT System 1 - Advance)
P0012 (VVT System 1 - Retard)
P0021 (VVT System 2 - Advance)
P0022 (VVT System 2 - Retard)
P0031, P0032, P0051, P0052 (A/F sensor heater - Sensor 1)
P0100 - P0103 (MAF meter)
P0115 - P0118 (ECT sensor)
P0120 - P0223, P2135 (TP sensor)
P0125 (Insufficient ECT for closed loop)
P0335 (CKP sensor)
P0340 (CMP sensor)
P0351 - P0356 (Igniter)
P0500 (VSS)

Fuel system status

Closed-loop

Battery voltage

11 V or more

Either of following conditions 1 or 2 set

-

1. Engine RPM

Below 1,100 rpm

2. Intake air amount per revolution

0.22 g/rev or more

Catalyst monitor

No executed

Purge-cut

Executing

Either of following conditions 1 or 2 met

-

1. Average between short-term fuel trim and long-term fuel trim

35 % or more (varies with ECT)

2. Average between short-term fuel trim and long-term fuel trim

-35 % or less (varies with ECT)

ES–160

1GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM

ES

•

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

Standard

NOTICE:
The Air-Fuel Ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen
(HO2) sensor has a maximum output delay of approximately 20 seconds.

•

Following the A/F CONTROL procedure enables technicians to check and graph the voltage outputs of
both the A/F and HO2 sensors.

•

To display the graph, select the following menu items on the tester: DIAGNOSIS / ENHANCED OBD II
/ ACTIVE TEST / A/F CONTROL / USER DATA / AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S
B2S2, and press the YES button and then the ENTER button followed by the F4 button.

HINT:
•

Read freeze frame data using an intelligent tester. Freeze frame data record the engine condition when
malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle
was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and
other data, from the time the malfunction occurred.

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

Case

A/F Sensor (Sensor 1)

Output Voltage

HO2 Sensor (Sensor 2)

Output Voltage

Main Suspected

Trouble Areas

1

Injection volume

+25 %

-12.5 %

Injection volume

+25 %

-12.5 %

-

Output voltage

More than 3.35 V

Less than 3.0 V

Output voltage

More than 0.55 V

Less than 0.4 V

2

Injection volume

+25 %

-12.5 %

Injection volume

+25 %

-12.5 %

•

A/F sensor

•

A/F sensor heater

•

A/F sensor circuit

Output voltage

Almost

no reaction

Output voltage

More than 0.55 V

Less than 0.4 V

3

Injection volume

+25 %

-12.5 %

Injection volume

+25 %

-12.5 %

•

HO2 sensor

•

HO2 sensor heater

•

HO2 sensor circuit

Output voltage

More than 3.35 V

Less than 3.0 V

Output voltage

Almost

no reaction

4

Injection volume

+25 %

-12.5 %

Injection volume

+25 %

-12.5 %

•

Injector

•

Fuel pressure

•

Gas leakage from exhaust
system

(Air-fuel ratio extremely lean or
rich)

Output voltage

Almost

no reaction

Output voltage

Almost

no reaction

1GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM

ES–161

ES

•

A low A/F sensor voltage could be caused by a rich air-fuel mixture. Check for conditions that would
cause the engine to run rich.

•

A high A/F sensor voltage could be caused by a lean air-fuel mixture. Check for conditions that would
cause the engine to run lean.

(a) Connect an intelligent tester to the DLC3.
(b) Turn the ignition switch ON and turn the tester ON.
(c) Select the following menu items: DIAGNOSIS /

ENHANCED OBD II / DTC INFO / CURRENT CODES.

(d) Read DTCs.

Result

HINT:
If any DTCs other than P0171, P0172, P0174 or P0175
are output, troubleshoot those DTCs first.

B

A

OK:

PCV hose is connected correctly and is not damaged.

NG

OK

(a) Check the air induction system for vacuum leakage.

OK:

No leakage from air induction system.

NG

OK

(a) Connect an intelligent tester to the DLC3.
(b) Start the engine and turn the tester ON.
(c) Warm up the engine at an engine speed of 2,500 rpm for

approximately 90 seconds.

(d) Select the following menu items: DIAGNOSIS /

ENHANCED OBD II / ACTIVE TEST / A/F CONTROL.

1

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0171, P0172, P0174 OR
P0175)

Display (DTC Output)

Proceed To

P0171, P0172, P0174 or P0175

A

P0171, P0172, P0174 or P0175 and other DTCs

B

GO TO DTC CHART (See page

ES-57

)

2

CHECK PCV HOSE CONNECTIONS

REPAIR OR REPLACE PCV HOSE

3

CHECK AIR INDUCTION SYSTEM

REPAIR OR REPLACE AIR INDUCTION
SYSTEM

4

PERFORM ACTIVE TEST USING INTELLIGENT TESTER (A/F CONTROL)

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1GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM

ES

(e) 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).

(f)

Monitor the voltage outputs of 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

Result:

Lean: During A/F CONTROL, the A/F sensor output
voltage (AFS) is consistently more than 3.35 V, and the
HO2 sensor output voltage (O2S) is consistently less
than 0.4 V.
Rich: During A/F CONTROL, the AFS is consistently less
than 3.0 V, and the O2S is consistently more than 0.55 V.
Lean/Rich: During A/F CONTROL of the ACTIVE TEST,
the output voltage of the heated oxygen sensor
alternates correctly.

B

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

Status

AFS B1S1

or

AFS B2S1

Status

O2S B1S2

or

O2S B2S2

A/F Condition and

A/F Sensor Condition

Misfires

Suspected Trouble Areas

Proceed To

Lean/Rich

Lean/Rich

Normal

-

-

C

Lean

Lean

Actual air-fuel ratio lean

May occur

•

PCV valve and hose

•

PCV hose connections

•

Injector blockage

•

Gas leakage from exhaust system

•

Air induction system

•

Fuel pressure

•

Mass Air Flow (MAF) meter

•

Engine Coolant Temperature (ECT)
sensor

A

Rich

Rich

Actual air-fuel ratio rich

-

•

Injector blockage or blockage

•

Gas leakage from exhaust system

•

Ignition system

•

Fuel pressure

•

MAF meter

•

ECT sensor

Lean

Lean/Rich

A/F sensor malfunction

-

•

A/F sensor

B

Rich

Lean/Rich

A/F sensor malfunction

-

•

A/F sensor

Go to step 11