Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Techstream only:

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 (A/F) sensor, Heated Oxygen (HO2) 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 Techstream.

Connect Techstream to the DLC3.
Start the engine and turn the tester on.
Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
On the tester, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
Perform the Control the Injection Volume for A/F Sensor 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 A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S B2S2) displayed on the tester.

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.

TYPICAL MALFUNCTION THRESHOLDS

Tester Display (Sensor)	Injection Volume	Status	Voltage
AFS B1S1 or AFS B2S1 (A/F)	+25 %	Rich	Less than 3.0 V
AFS B1S1 or AFS B2S1 (A/F)	-12.5 %	Lean	More than 3.35 V
O2S B1S2 or O2S B2S2 (HO2)	+25 %	Rich	More than 0.55 V
O2S B1S2 or 02S B2S2 (HO2)	-12.5 %	Lean	Less than 0.4 V

NOTE: 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.

A/F SENSOR RATIO OUTPUT REFERENCE

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	Fuel pressure Gas leakage from exhaust system (Air fuel ratio extremely lean or rich)

Following the Control the Injection Volume for A/F Sensor procedure enables technicians to check and graph the voltage outputs of both the A/F and HO2 sensors.
To display the graph, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor/A/F B1 S1 and O2S B1 S2 or A/F B2 S1 and O2S B2 S2; then press the graph button on the Data List view.

HINT:

Read freeze frame data using 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 (See FREEZE FRAME DATA ).
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 rich air-fuel mixture. Check for conditions that would cause the engine to run lean.

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO P0171, P0172, P0174, P0175, P1170 OR P117B)

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

Read DTCs.

Result

RESULT REFERENCE CHART

Display (DTC output)	Proceed to
P0171, P0172, P0174, P0175, P1170 or P117B	A
P0171, P0172, P0174 or P0175, P1170, P117B and other DTCs	B

HINT:

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

B: GO TO DTC CHART

A: Go to next step.

PERFORM SYSTEM CHECK (D-4S TEST)

Connect Techstream to the DLC3.
Start the engine and turn Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Way / Port.
Read the value 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 and ECT / Active Test / Control the Injection Way / Direct.

Read the value 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 REFERENCE CHART

Item		Proceed to
PORT	DIRECT	Proceed to
OK	OK	A
OK	NG	B
NG	OK	C
NG	NG	D

B: Go to step 20

C: Go to step 24

D: Go to step 5

A: Go to next step.

CHECK IF VEHICLE HAS RUN OUT OF FUEL IN PAST
YES: DTC CAUSED BY RUNNING OUT OF FUEL

NO: Go to next step.

CHECK FUEL PUMP RELAY

Remove the F/PMP relay from the engine room No. 2.

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

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
3 - 4	10 kΩ or higher
3 - 4	Below 1 Ω (when battery voltage applied to terminals 1 and 2)

Fig 1: Identifying Terminals Of Fuel Pump Relay

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE RELAY

OK: CHECK FOR INTERMITTENT PROBLEMS

CHECK PCV HOSE
OK:

PCV hose is connected correctly and is not damaged.

NG: REPAIR OR REPLACE PCV HOSE

OK: Go to next step.
CHECK AIR INDUCTION SYSTEM
1. Check the air induction system for vacuum leakage.
  OK:
  
  No leakage from air induction system.
NG: REPAIR OR REPLACE AIR INDUCTION SYSTEM

OK: Go to next step.

PERFORM ACTIVE TEST BY TECHSTREAM (A/F CONTROL)

Connect Techstream to the DLC3.
Start the engine and turn the tester on.
Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
On the tester, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
Perform the Control the Injection Volume for A/F Sensor 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 A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S B2S2) displayed on the tester.

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.

TESTER DISPLAY INJECTION VOLUME CHART

Tester Display (Sensor)	Injection Volume	Status	Voltage
AFS B1S1 or AFS B2S1 (A/F)	+25 %	Rich	Less than 3.0 V
AFS B1S1 or AFS B2S1 (A/F)	-12.5 %	Lean	More than 3.35 V
O2S B1S2 or O2S B2S2 (HO2)	+25 %	Rich	More than 0.55 V
O2S B1S2 or O2S B2S2 (HO2)	-12.5 %	Lean	Less than 0.4 V

Result

RESULT REFERENCE CHART

Status AFS B1S1 or AFS B2S1	Status O2S B1S2 or O2S B2S2	A/F Condition and A/F 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 for port injection 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	-	Gas leakage from exhaust system Ignition system Fuel pressure MAF meter ECT sensor	A
Lean	Lean/Rich	A/F sensor malfunction	-	A/F sensor	B
Rich	Lean/Rich	A/F sensor malfunction	-	A/F sensor	B
Lean: During Control the Injection Volume for A/F Sensor, 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 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 11

A: Go to next step.

READ VALUE OF TECHSTREAM (COOLANT TEMP)
1. Connect Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn the tester on.
3. Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
4. Read the Coolant Temp 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

OK: Go to next step.
READ VALUE OF TECHSTREAM (MAF)
1. Read the value using the Techstream (MAF).
  NOTE:
  - Turn off the engine.
  - Perform the inspection with the vehicle indoors and on a level surface.
  - Perform the inspection of the MAF meter while it is installed to the air cleaner case (installed to the vehicle).
  - During the test, do not use the exhaust air duct to perform suction on the exhaust pipe.
  1. Turn the engine switch on (ACC).
  2. Turn the engine switch on (IG) (do not run the engine).
  3. Turn the tester ON.
  4. Select the following menu items: Powertrain / Engine and ECT / Data List / MAR
  5. Wait 30 seconds, and read the values on the Techstream.
    Standard condition:
    
    Less than 0.36 g/sec.
NG: REPLACE MASS AIR FLOW METER

OK: Go to next step.
CHECK FOR EXHAUST GAS LEAK
OK:

No gas leakage.

NG: REPAIR OR REPLACE EXHAUST SYSTEM

OK: Go to next step.

INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)

Disconnect the E42 or E38 A/F 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
HA1A (1) -+B (2)	20°C (68°F)	1.8 Ω to 3.4 Ω
HA1A (1) - A1A- (4)	-	10 kΩ or higher

Fig 2: Identifying Terminals Of E42 Or E38 A/F Sensor Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard resistance (Bank 2 sensor 1)

TESTER CONNECTION SPECIFIED CONDITION CHART

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

Reconnect the A/F sensor connector.

NG: REPLACE AIR FUEL RATIO SENSOR

OK: Go to next step.

INSPECT A/F RELAY

Remove the A/F relay from the engine room R/B No. 2.

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

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
3 - 5	10 kΩ or higher
3 - 5	Below 1 Ω (when battery voltage applied to terminals 1 and 2)

Reinstall the A/F relay. NG

Fig 3: Identifying Terminals Of A/F Relay

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE A/F RELAY

OK: Go to next step.

CHECK HARNESS AND CONNECTOR (A/F SENSOR - ECM)

Disconnect the E42 and E38 A/F sensor connectors.
Turn the engine switch on (IG).

Measure the voltage according to the value (s) in the table below.

Standard voltage

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
+B (E42-2) - Body ground	9 to 14 V
+B (E38-2) - Body ground	9 to 14 V

Turn the engine switch off.
Disconnect the E6 ECM connector.

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

Fig 4: Identifying Terminals Of E42 And E38 A/F Sensor Connectors

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard resistance (Check for open)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
HA1A (E42-1) - HA1A (E6-6)	Below 1 Ω
A1A+ (E42-3) - A1A+ (E6-18)	Below 1 Ω
A1A- (E42-4) - A1A- (E6-17)	Below 1 Ω
HA2A (E38-1) - HA2A (E6-4)	Below 1 Ω
A2A+ (E38-3) - A2A+ (E6-28)	Below 1 Ω
A2A- (E38-4) - A2A- (E6-27)	Below 1 Ω

Standard resistance (Check for short)

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Specified Condition
HA1A (E42-1) or HA1A (E6-6) - Body ground	10 kΩ or higher
A1A+ (E42-3) or A1A+ (E6-18) - Body ground	10 kΩ or higher
A1A- (E42-4) or A1A- (E6-17) - Body ground	10 kΩ or higher
HA2A (E38-1) or HA2A (E6-4) - Body ground	10 kΩ or higher
A2A+ (E38-3) or A2A+ (E6-28) - Body ground	10 kΩ or higher
A2A- (E38-4) or A2A- (E6-27) - Body ground	10 kΩ or higher

Reconnect the ECM connector.
Reconnect the A/F sensor connector.

Fig 5: A/F Sensor Heater (B1/S1) Circuit Diagram
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step.

REPLACE AIR FUEL RATIO SENSOR
PERFORM COMFORTABLE AIR SEAT SYSTEM

Fig 6: Vehicle Speed Driving Pattern
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. Connect Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn the tester on.
3. Clear DTCs (See DTC CHECK / CLEAR ).
4. Switch the ECM from normal mode to check mode using the tester (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 1,400 rpm and 3,200 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 (DTC P0171, P0172, P0174, P0175, P1170 OR P117B)

On Techstream, enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

Read DTCs.

Result

RESULT REFERENCE CHART

Display (DTC output)	Proceed to
No output	A
P0171, P0172, P0174, P0175, P1170 or P117B	B

A: END

B: Go to next step.

CHECK FUEL PRESSURE (LOW PRESSURE)
1. Check the fuel pressure (See ON-VEHICLE INSPECTION ).
OK: REPLACE ECM

NG: Go to next step.
CHECK FUEL PUMP OPERATION
1. Check the fuel pump operation (See ON-VEHICLE INSPECTION ).
NG: REPLACE FUEL PUMP

OK: Go to next step.
CHECK FUEL LEAK (LOW PRESSURE SIDE)
OK:

No leakage

NG: REPAIR OR REPLACE FUEL SYSTEM

OK: CHECK AND REPLACE FUEL PUMP, PRESSURE REGULATOR, FUEL PIPE LINE AND FILTER
CHECK FUEL PRESSURE SENSOR
1. Connect Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn the tester on.
3. Start the engine.
4. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.
5. While revving the engine, check that the fuel pressure fluctuates.
  Standard:
  
  Idling:
  
  3 to 5 MPa
  
  2,500 rpm (No load):
  
  6 to 10 MPa
  
  HINT:
  
  The A/C switch and all accessory switches should be OFF, and the transmission gear selector lever should be in the N or P position, and the engine should be fully warmed up.
NG: REPAIR OR REPLACE FUEL SYSTEM FOR HIGH PRESSURE (REFER TO DTC P0087 AND P0088 )

OK: Go to next step.

PERFORM SYSTEM CHECK (D-4S TEST)

Connect Techstream to the DLC3.
Start the engine and turn Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Way / Port.
Read the value 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 and ECT / Active Test / Control the Injection Way / Direct.
HINT:

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

Read the value Short FT #1, Long FT #1, Short FT #2, Long FT #2 and Fuel Pump Duty (D4).

Result

RESULT REFERENCE 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

B: Go to step 23

C: REPLACE ECM

PERFORM SYSTEM CHECK (D-4S TEST)

Connect Techstream to the DLC3.
Start the engine and turn Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Way / Port.
Read the value 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 and ECT / Active Test / Control the Injection Way / Direct.
HINT:

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

Read the value SHORT FT #1, LONG FT #1, Short FT #2, Long FT #2 and Fuel Pump Duty (D4).

Result

RESULT REFERENCE CHART

Item			Proceed to
Fuel Pump Duty (D4)4	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 FOR DIRECT INJECTION (BANK 1)

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

D: CHECK FOR INTERMITTENT PROBLEMS

A: REPLACE FUEL INJECTOR FOR DIRECT INJECTION (ALL CYLINDER)

CHECK RELIEF VALVE

Connect Techstream to the DLC3.
Turn the engine switch on (IG) and turn the tester on.
Start the engine.
Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Press.

Check that the fuel pressure fluctuates when the fuel hose is pressed with your fingers.

Result

RESULT REFERENCE CHART

Inspection Result	Proceed to
Pressing the hose raises the fuel pressure slightly	A
Fuel pressure does not fluctuate	B

OK: REPLACE RELIEF VALVE

B: REPLACE FUEL PUMP FOR HIGH PRESSURE

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

OK: REPLACE ECM