Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

HINT

Malfunctioning areas can be identified by performing the Control the Injection Volume for A/F sensor function provided in the Active Test The Control the Injection Volume for A/F sensor function can help to determine whether the air fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning

The following instructions describe how to conduct the Control the Injection Volume for A/F sensor operation using the Techstream

Connect the Techstream to the DLC3.
Start the engine and turn the Techstream ON
Warm up the engine at an engine speed of 2000 rpm for approximately 90 seconds.
On the Techstream, enter the following menus Powertrain / Engine / Active Test / Control the Injection Volume for A/F sensor
Perform the Active Test operation with the engine in an idling condition (press the RIGHT or LEFT button to change the fuel injection volume.)
Monitor the output voltages of the air fuel ratio sensors and heated oxygen sensors (AFS B1 S1 and O2S B1 S2 or AFS B2 S1 and O2S B2 S2) displayed on the Techstream

HINT

The Control the Injection Volume for A/F sensor 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.

INSPECTION PROCEDURE CHART

Tester Display (Sensor)	Injection Volume	Status	Voltage
AFS B1 S1 or AFS B2 S1 (Air fuel ratio)	+25%	Rich	Less than 3 0V
AFS B1 S1 or AFS B2 S1 (Air fuel ratio)	-12 5%	Lean	More than 3 35 V
O2S B1 S2 or O2S B2 S2 (Heated oxygen)	+25%	Rich	More than 0 55 V
O2S B1 S2 or O2S B2 S2 (Heated oxygen)	-12 5%	Lean	Less than 0 4V

NOTE: The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.

AIR FUEL RATIO SENSOR REFERENCE CHART

Case	Air Fuel Ratio Sensor (Sensor 1) Output Voltage	Heated Oxygen Sensor (Sensor 2) Output Voltage	Main Suspected Trouble Area
1	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	-
2	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Air fuel ratio sensor Air fuel ratio sensor heater Air fuel ratio sensor circuit
3	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Heated oxygen sensor Heated oxygen sensor heater Heated oxygen sensor circuit
4	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002	Injector assembly Fuel pressure Gas leaks from exhaust system (Air-fuel ratio extremely rich or lean)

Following the Control the Injection Volume for A/F sensor procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio sensors and heated oxygen sensors.
To display the graph, enter the following menus. Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / A/F Control System / AFS B1 S1 and O2S B1 S2 or AFS B2 S1 and O2S B2 S2

HINT

Read freeze frame data using the Techstream The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction
A low air fuel ratio sensor voltage could be caused by a rich air fuel mixture Check for conditions that would cause the engine to run rich
A high air fuel ratio sensor voltage could be caused by a lean air fuel mixture Check for conditions that would cause the engine to run lean

CHECK ANY OTHER DTCS OUTPUT

Connect the Techstream to the DLC3
Turn the engine switch on (IG) and turn the Techstream ON
Enter the following menus. Powertrain / Engine / Trouble Codes

Read the DTCs

Result

RESULT CHART

Result	Proceed to
DTC P0171, P0172, P0174, P0175, P1170 and/or P117B are output	A
DTC P0171, P0172, P0174, P0175, P1170 and/or P117B and other DTCs are output	B

HINT

If any DTCs other than P0171, P0172, P0174, P0175, P1170 or P117B are output, troubleshoot those DTCs first

B: GO TO DTC CHART (See DIAGNOSTIC TROUBLE CODE CHART )

A: Go to Next Step

READ VALUE USING TECHSTREAM

Connect the Techstream to the DLC3
Start the engine and turn the Techstream ON
Enter the following menus Powertrain / Engine / Active Test / Control the Injection Way / Port
Read the value.
1. Enter Data List / A/F Control System / Short FT #1 and Long FT #1 and/or Short FT #2 and Long FT #2.
  OK: Short FT #1, #2 + Long Ft #1, #2 = Between -19% and +19%
Enter the following menus Powertrain / Engine / Active Test / Control the Injection Way / Direct.

Read the value

Enter Data List / A/F Control System / Short FT #1 and Long FT #1 and/or Short FT #2 and Long FT #2

OK: Short FT #1, #2 + Long Ft #1, #2 = Between -19% and +19%

Result

RESULT CHART

Item		Proceed to
Port	Direct	Proceed to
OK	OK	A
OK	NG	B
NG	OK	C
NG	NG	D

B: Go to step 19

C: Go to step 25

D: Go to step 4

A: Go to Next Step

CHECK IF VEHICLE HAS RUN OUT OF FUEL IN PAST
1. Has the vehicle run out of fuel in the past?
NO: CHECK FOR INTERMITTENT PROBLEMS (See CHECK FOR INTERMITTENT PROBLEMS )

YES: DTC CAUSED BY RUNNING OUT OF FUEL
CHECK PCV HOSE
OK: PCV hose is connected correctly and is not damaged.

NG: REPAIR OR REPLACE PCV HOSE (See REMOVAL )

OK: Go to Next Step
CHECK INTAKE SYSTEM
1. Check the intake system for vacuum leaks (See ON-VEHICLE INSPECTION )
  OK: No leaks from intake system.
NG: REPAIR OR REPLACE INTAKE SYSTEM (See ON-VEHICLE INSPECTION )

OK: Go to Next Step

PERFORM ACTIVE TEST USING TECHSTREAM

Connect the Techstream to the DLC3.
Start the engine and turn the Techstream ON.
Warm up the engine at an engine speed of 2000 rpm for approximately 90 seconds.
Enter the following menus. Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor
Perform the Active Test operation with the engine in an idling condition (press the RIGHT or LEFT button to change the fuel injection volume)

Monitor the output voltages of the air fuel ratio sensors and heated oxygen sensors (AFS B1 S1 and O2S B1 S2 or AFS B2 S1 and O2S B2 S2) displayed on the Techstream

HINT:

The Control the Injection Volume for A/F sensor 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

INSPECTION PROCEDURE CHART

Tester Display (Sensor)	Injection Volume	Status	Voltage
AFS B1 S1 or AFS B2 S1 (Air fuel ratio)	+25%	Rich	Less than 3 0V
AFS B1 S1 or AFS B2 S1 (Air fuel ratio)	-12 5%	Lean	More than 3 35 V
O2S B1 S2 or O2S B2 S2 (Heated oxygen)	+25%	Rich	More than 0 55 V
O2S B1 S2 or O2S B2 S2 (Heated oxygen)	-12 5%	Lean	Less than 0 4V

Result

RESULT CHART

Status AFS B1 S1 or AFS B2 S1	Status O2S B1 S2 or O2S B2 S2	Air Fuel Ratio Condition and Air Fuel Ratio Sensor Condition	Misfire	Suspected Trouble Area	Proceed to
Lean/Rich	Lean/Rich	Normal	-	-	A
Lean	Lean	Actual air fuel ratio lean	May occur	PCV valve and hose PCV hose connections Injector assembly for port injection Injector assembly for direct injection Gas leaks from exhaust system Intake system Fuel pressure Mass air flow meter sub-assembly Engine coolant temperature sensor	A
Rich	Rich	Actual air fuel ratio rich	-	Injector assembly for port injection Injector assembly for direct injection Gas leaks from exhaust system Ignition system Fuel pressure Mass air flow meter sub-assembly Engine coolant temperature sensor	A
Lean	Lean/Rich	Air fuel ratio sensor malfunction	-	Air fuel ratio sensor	B
Rich	Lean/Rich	Air fuel ratio sensor malfunction	-	Air fuel ratio sensor	B

Lean

During Control the Injection Volume for A/F sensor, the air fuel ratio sensor output voltage (AFS) is consistently more than 3 35 V, and the heated oxygen sensor output voltage (O2S) is consistently less than 0 4V

Rich.

During Control the Injection Volume for A/F sensor, the AFS is consistently less than 3.0 V, and the O2S is consistently more than 0 55 V

B: Go to step 10

A: Go to Next Step

READ VALUE USING TECHSTREAM (COOLANT TEMP)
1. Connect the Techstream to the DLC3
2. Turn the engine switch on (IG) and turn the Techstream ON
3. Enter the following menus Powertrain / Engine / Data List / Coolant Temp
4. Read the Data List twice, when the engine is both cold and warmed up.
  Standard: With cold engine:
  
  Same as ambient air temperature.
  
  With warm engine: Between 75 and 95°C (167 and 203°F)
NG: REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See REMOVAL )

OK: Go to Next Step
INSPECT MASS AIR FLOW METER SUB-ASSEMBLY
1. Inspect the mass air flow meter sub-assembly (See REMOVAL ).
NG: REPLACE MASS AIR FLOW METER SUB-ASSEMBLY (See REMOVAL )

OK: Go to Next Step
CHECK FOR EXHAUST GAS LEAK
1. Check for exhaust gas leaks
  OK: No gas leaks.
NG: REPAIR OR REPLACE EXHAUST SYSTEM

OK: Go to Next Step

INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)

Disconnect the air fuel ratio sensor connector

Measure the resistance according to the value(s) in the table below

Standard Resistance (Bank 1 Sensor 1)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
1 (HA1A) - 2 (+B)	20°C (68°F)	1 8 to 3.4 Ω
1 (HA1A) - 4 (A1A-)	Always	10 kΩ or higher

Standard Resistance (Bank 2 Sensor 1)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
1 (HA2A) - 2 (+B)	20°C (68°F)	1.8 to 3.4 Ω
1 (HA2A) - 4 (A2A-)	Always	10 kΩ or higher

Reconnect the air fuel ratio sensor connector

Fig 1: Identifying Air Fuel Ratio Sensor Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE AIR FUEL RATIO SENSOR (See REMOVAL )

OK: Go to Next Step

CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)

Disconnect the air fuel ratio sensor connector.
Disconnect the ECM connectors.

Measure the resistance according to the value(s) in the table below

Standard Resistance (Check for Open)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
E42-1(HA1A) - E6-5 (HA1A)	Always	Below 1 Ω
E42-3 (A1A+) - E5-23 (A1A+)	Always	Below 1 Ω
E42-4 (A1A-) - E5-22 (A1A-)	Always	Below 1 Ω
E38-1 (HA2A) - E6-6 (HA2A)	Always	Below 1 Ω
E38-3 (A2A+) - E5-21 (A2A+)	Always	Below 1 Ω
E38-4 (A2A-) - E5-20 (A2A-)	Always	Below 1 Ω

Standard Resistance (Check for Short)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
E42-1(HA1A) or E6-5 (HA1A) - Body ground	Always	10 kΩ or higher
E42-3 (A1A+) or E5-23 (A1A+) - Body ground	Always	10 kΩ or higher
E42-4 (A1A-) or E5-22 (A1A-) - Body ground	Always	10 kΩ or higher
E38-1 (HA2A) or E6-6 (HA2A) - Body ground	Always	10 kΩ or higher
E38-3 (A2A+) or E5-21 (A2A+) - Body ground	Always	10 kΩ or higher
E38-4 (A2A-) or E5-20 (A2A-) - Body ground	Always	10 kΩ or higher

Fig 2: Identifying Air Fuel Ratio Sensor Connector And ECM Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

REPLACE AIR FUEL RATIO SENSOR
1. Replace the air fuel ratio sensor (See REMOVAL ).
PERFORM CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
  
  Fig 3: Vehicle Speed - Driving Pattern
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the engine switch on (IG) and turn the Techstream ON
3. Clear DTCs (See DTC CHECK/CLEAR )
4. Switch the ECM from normal mode to check mode using the Techstream (See CHECK MODE PROCEDURE ).
5. Start the engine and warm it up with all the accessories switched off. (Procedure "A")
6. Drive the vehicle at between 38 mph and 75 mph (60 km/h and 120 km/h) and at an engine speed of between 1400 rpm and 2000 rpm for 3 to 5 minutes (Procedure "B")
  HINT
  
  If the system is still malfunctioning, the MIL will be illuminated during procedure "B".
  
  NOTE: If the conditions in this test are not strictly followed, no malfunction will be detected.

CHECK WHETHER DTC OUTPUT RECURS

Connect the Techstream to the DLC3
Turn the engine switch on (IG) and turn the Techstream ON
Enter the following menus Powertrain / Engine / Trouble Codes

Read the DTCs.

Result

RESULT CHART

Result	Proceed to
DTC is not output	A
P0171, P0172, P0174, P0175, P1170 and/or P117B are output	8

A: END

B: Go to Next Step

CHECK FUEL PRESSURE (LOW PRESSURE)
1. Check the fuel pressure (See ON-VEHICLE INSPECTION )
NG: Go to step 16

OK: REPLACE ECM (See REMOVAL )
CHECK FUEL PUMP OPERATION
1. Check the fuel pump operation (See ON-VEHICLE INSPECTION )
NG: REPAIR OR REPLACE FUEL PUMP CONTROL CIRCUIT (See DISASSEMBLY )

OK: Go to Next Step
CHECK FUEL LEAK (LOW PRESSURE SIDE)
1. Check for fuel leaks (low pressure side)
  OK: No leaks.
NG: REPAIR OR REPLACE FUEL SYSTEM

OK: Go to Next Step
CHECK FUEL LINE
1. Check the fuel line for leaks or blockage (See PRECAUTION )
  OK: No leaks or blockage.
NG: REPAIR OR REPLACE FUEL LINE (See PRECAUTION )

OK: CHECK AND REPLACE FUEL SYSTEM (FUEL PRESSURE REGULATOR, FUEL FILTER)
CHECK FUEL PRESSURE SENSOR
1. Connect the Techstream to the DLC3
2. Turn the engine switch on (IG) and turn the Techstream ON.
3. Start the engine
4. Enter the following menus. Powertrain / Engine / Data List / Fuel Press
5. While revving the engine, check that the fuel pressure fluctuates
  Standard: Idling:
  
  3.5 to 4.5 MPa
  
  2000 rpm (No load):
  
  7 to 9 MPa
  
  HINT
  
  The A/C switch and all accessory switches should be off, and the shift lever should be in N or P, and the engine should be fully warmed up.
NG: Go to step 22

OK: Go to Next Step

READ VALUE USING TECHSTREAM

Connect the Techstream to the DLC3
Start the engine and turn the Techstream ON
Enter the following menus. Powertrain / Engine / Active Test / Control the Injection way / Direct
HINT.

The A/C switch and all accessory switches should be off, and the shift lever should be in N or P, and the engine should be fully warmed up.

Read the value

Enter Data List / A/F Control System / Short FT #1, Long FT #1, Short FT #2, Long FT #2 and Fuel Pump Duty (D4)

Result

RESULT CHART

Item			Proceed to
Fuel Pump Duty (D4)	Short FT #1 + Long FT #1	Short FT #2 + Long FT #2	Proceed to
40% or more	-20% or less	-20% or less	A
10% or less	+20% or more	+20% or more	A
40% or more	+20% or more	+20% or more	B
10% or less	-20% or less	-20% or less	C
10% to 40%	-	-	D

A: REPLACE FUEL PRESSURE SENSOR (See REMOVAL )

B: Go to step 24

C: REPLACE ECM (See REMOVAL )

D: Go to Next Step

READ VALUE USING TECHSTREAM

Connect the Techstream to the DLC3
Start the engine and turn the Techstream ON.
Enter the following menus Powertrain / Engine / Active Test / Control the Injection way / Direct
HINT

The A/C switch and all accessory switches should be OFF, and the shift lever should be in N or P, and the engine should be fully warmed up.

Read the value of Data List.

Enter Data List / A/F Control System / Short FT #1, Long FT #1, Short FT #2, Long FT #2 and Fuel Pump Duty (D4)

Result

RESULT CHART

Item			Proceed to
Fuel Pump Duty (D4)	Short FT #1 + Long FT #1	Short FT #2 + Long FT #2	Proceed to
10% to 40%	-25% or less	-25% or less	A
10% to 40%	-25% or less	-25% to +25%	B
10% to 40%	-25% to +25%	-25% or less	C
10% to 40%	+30% or more	+30% or more	A
10% to 40%	+25% or more	-25% to +25%	B
10% to 40%	-25% to +25%	+25% or more	C
10% to 40%	-25% to +25%	-25% to +25%	D

B: REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION (BANK 1)) (See REMOVAL )

C: REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION (BANK 2)) (See REMOVAL )

D: CHECK FOR INTERMITTENT PROBLEMS (See CHECK FOR INTERMITTENT PROBLEMS )

A: REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION) (See REMOVAL )

CHECK MISFIRE COUNT

Connect the Techstream to the DLC3
Turn the engine switch on (IG) and turn the Techstream ON
Start the engine
Enter the following menus Powertrain / Engine / Active Test / Control the Injection Way / Direct
Allow the engine to idle

Monitor all of the misfire count values that are displayed on the Techstream Powertrain / Engine / Data List / Misfire / Cylinder #1 Misfire Count to Cylinder #8 Misfire Count

If no misfire counts occur for any of the cylinders, perform the following procedure

Move the shift lever to D.

Monitor all of the misfire rate values that are displayed on the Techstream

Result

RESULT CHART

Misfire Count	Proceed to
No misfire counts, or misfire counts occur randomly in all cylinders	A
Misfire counts occur in particular cylinder	B

B: REPLACE FUEL INJECTOR ASSEMBLY (FOR DIRECT INJECTION) (See REMOVAL )

A: Go to Next Step

INSPECT INJECTOR DRIVER (NO. 1 AND NO. 2)

Turn the engine switch off.
Replace the No 1 and No 2 injector drivers with known good ones from another vehicle
NOTE: Do not disconnect and reconnect the connectors with the engine switch on (IG), as the injector driver (EDU) may be damaged.
Connect the Techstream to the DLC3.
Start the engine
Clear DTCs (See DTC CHECK/CLEAR )
Perform the driving test.
Enter the following menus Powertrain / Engine / Trouble Codes

Read the DTCs

Result

RESULT CHART

Result	Proceed to
DTC P0171, P0172, P0174, P0175, P1170 and/or P117B are output	A
DTC is not output	B

B: REPLACE INJECTOR DRIVER (NO. 1 AND NO. 2) (See REMOVAL )

A: Go to Next Step

INSPECT FUEL RELIEF VALVE ASSEMBLY

Connect the Techstream to the DLC3
Turn the engine switch on (IG) and turn the Techstream ON
Start the engine
Enter the following menus Powertrain / Engine / Data List / Fuel Press
Record the Fuel Press value
Turn the engine switch off
Wait for 10 seconds.
Turn the engine switch on (IG) and turn the Techstream ON
Enter the following menus: Powertrain / Engine / Data List / Fuel Press

Compare the Fuel Press value recorded with the engine running to the Fuel Press value currently shown on the Techstream

Result

RESULT CHART

Inspection Result	Proceed to
Fuel Press value drops	A
Fuel Press value is maintained	B

A: REPLACE FUEL RELIEF VALVE ASSEMBLY (See REMOVAL )

B: REPLACE FUEL PUMP ASSEMBLY (FOR HIGH PRESSURE) (See REMOVAL )

CHECK FUEL INJECTOR ASSEMBLY (FOR PORT INJECTION)
1. Check the injection volume (whether fuel volume is high or low, and whether injection pattern is poor) (See INSPECTION )
NG: REPLACE FUEL INJECTOR ASSEMBLY (FOR PORT INJECTION) (See REMOVAL )

OK: REPLACE ECM (See REMOVAL )