Toyota Tundra. Manual — part 1542

RESULT REFERENCE

HINT:

A normal HO2 sensor voltage (O2S B1 S2 or O2S B2 S2) 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.

Fig. 99: HO2 Sensor Voltage Graph
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: Go to step 22

OK: Go to Next Step

8. CHECK FOR EXHAUST GAS LEAK

a. Check for exhaust gas leak.

OK: No gas leakage.

NG: REPAIR OR REPLACE EXHAUST GAS LEAK POINT

OK: Go to Next Step

9. CHECK FUEL PRESSURE

a. Check the fuel pressure (see ON-VEHICLE INSPECTION ).

NG: GO TO FUEL PRESSURE SWITCHING SYSTEM

OK: Go to Next Step

10. INSPECT FUEL INJECTOR (INJECTION AND VOLUME)

Display Item (Sensor)

Voltage Variation

Proceed to

AFS Voltage B1 S1 (A/F)
AFS Voltage B2 S1 (A/F)

Alternates between more and less than 3.3 V

OK

Remains at more than 3.3 V

NG

Remains at less than 3.3 V

NG

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

a. Check the injection volume (see INSPECTION ).

NG: REPLACE FUEL INJECTOR (See REMOVAL )

OK: Go to Next Step

11. INSPECT MASS AIR FLOW METER

a. Inspect the mass air flow meter (see REMOVAL ).

NG: REPLACE MASS AIR FLOW METER (See REMOVAL )

OK: Go to Next Step

12. INSPECT ENGINE COOLANT TEMPERATURE SENSOR

a. Inspect the engine coolant temperature sensor (see INSPECTION ).

NG: REPLACE ENGINE COOLANT TEMPERATURE SENSOR (See REMOVAL )

OK: Go to Next Step

13. INSPECT PCV HOSE

a. Check the PCV hose connections (see ON-VEHICLE INSPECTION ).

OK: PCV hose is connected correctly and is not damaged.

NG: REPAIR OR REPLACE PCV HOSE (See PCV VALVE )

OK: Go to Next Step

14. CHECK AIR INDUCTION SYSTEM

a. Check the air induction system for vacuum leakage (see ON-VEHICLE INSPECTION ).

OK: No leakage from air induction system.

NG: REPAIR OR REPLACE AIR INDUCTION SYSTEM (See REMOVAL )

OK: Go to Next Step

15. CHECK SPARKS AND IGNITION (See INSPECTION PROCEDURE )

NG: REPAIR OR REPLACE IGNITION SYSTEM (See REMOVAL )

OK: REPLACE ECM (See REMOVAL )

16. CHECK FOR EXHAUST GAS LEAK

a. Check for exhaust gas leak.

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

OK: No gas leakage.

NG: REPAIR OR REPLACE EXHAUST GAS LEAKAGE POINT

OK: Go to Next Step

17. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE) (See INSPECTION

PROCEDURE )

NG: REPLACE HEATED OXYGEN SENSOR (See REMOVAL )

OK: Go to Next Step

18. INSPECT INTEGRATION RELAY (EFI RELAY) (See INSPECTION PROCEDURE )

NG: REPLACE INTEGRATION RELAY (See ON-VEHICLE INSPECTION )

OK: Go to Next Step

19. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)

a. Disconnect the D31 or D32 HO2 sensor connector.

Fig. 100: Identifying Terminals Of D31 Or D32 HO2 Sensor Connectors
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

b. Turn the ignition switch to ON.

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

Standard voltage

VOLTAGE SPECIFIED CONDITION

d. Turn the ignition switch off.

Tester Connection

Switch Condition Specified Condition

D31-2 (+B) - Body ground Ignition switch ON

9 to 14 V

D32-2 (+B) - Body ground Ignition switch ON

9 to 14 V

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

e. Disconnect the D74 ECM connector.

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

Standard resistance

RESISTANCE SPECIFIED CONDITION

Fig. 101: Oxygen Sensor Heater Control - Circuit Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

20. REPLACE HEATED OXYGEN SENSOR

a. Replace the heated oxygen sensor (see REMOVAL ).

21. PERFORM CONFIRMATION DRIVING PATTERN

Tester Connection

Condition Specified Condition

D31-1 (HT1B) - D74-45 (HT1B)

Always

Below 1 ohms

D31-3 (OX1B) - D74-114 (OX1B)

Always

Below 1 ohms

D31-4 (E1) - D74-115 (EX1B)

Always

Below 1 ohms

D32-1 (HT2B) - D74-44 (HT2B)

Always

Below 1 ohms

D32-3 (OX2B) - D74-112 (OX2B)

Always

Below 1 ohms

D32-4 (E1) - D74-113 (EX2B)

Always

Below 1 ohms

D31-1 (HT1B) or D74-45 (HT1B) - Body ground

Always

10 kohms or higher

D31-3 (0X1 B) or D74-114 (OX1B) - Body ground Always

10 kohms or higher

D32-1 (HT2B) or D74-44 (HT2B) - Body ground

Always

10 kohms or higher

D32-3 (OX2B) or D74-112 (OX2B) - Body ground Always

10 kohms or higher

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra