Toyota Tundra. Manual — part 1160

P0141 and P0161:

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

P0037 and P0057:

TYPICAL MALFUNCTION THRESHOLDS

P0038 and P0058:

TYPICAL MALFUNCTION THRESHOLDS

P0141 and P0161 (Heater performance monitor check)

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

COMPONENT OPERATING RANGE

MONITOR RESULT

Refer to CHECKING MONITOR STATUS .

WIRING DIAGRAM

Refer to DTC P0136 .

One of the following conditions is met:

Condition A or B

A. All of the following conditions are met:

Condition 1, 2, 3,4 and 5

1. Battery voltage

10.5 V or more

2. Fuel cut

OFF

3. Time after fuel cut ON to OFF

30 seconds or wore

4. Accumulated heater ON time

100 seconds or more

5. Learned heater OFF current operation

Completed

B. Duration that rear heated oxygen sensor impedance is less than 15 kohms

2 seconds or more

Heater current

Less than 0.3 A

One of the following conditions is met:

Condition A or B

A. Learned heater OFF current

More than 2 A

B. Hybrid IC high current limiter port

Fail

Accumulated heater resistance Varies with sensor element temperature (Example: More than 23 ohms)

Heated Oxygen (HO2) sensor
heater current

0.4 to 1 A (when engine idles, HO2 sensor warmed up and battery
voltage 11 to 14 V)

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

INSPECTION PROCEDURE

HINT:

Read freeze frame data using the Techstream. Freeze frame data records 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.

1. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

a. Disconnect the D31*1 or D32*2 heated oxygen (HO2) sensor connector.

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

Standard resistance (Bank 1 sensor 2)

TESTER CONNECTION SPECIFIED CONDITION

Standard resistance (Bank 2 sensor 2)

TESTER CONNECTION SPECIFIED CONDITION

NG : REPLACE HEATED OXYGEN SENSOR (See REMOVAL )

Fig. 47: Identifying Heated Oxygen (HO2) Sensor Connector Terminals

Tester Connection Condition Specified Condition

1(HT1B) - 2(+B) 20°C (68°F)

11 to 16 ohms

1 (HT1B) - 4(E2)

Always

10 kohms or higher

Tester Connection Condition Specified Condition

1 (HT2B) - 2 (+B) 20°C (68°F)

11 to 16 D

1 (HT2B) - 4 (E2)

Always

10 kohms or higher

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

OK : Go to next step

2. CHECK TERMINAL VOLTAGE (+B OF HO2 SENSOR)

a. Disconnect the D31*1 or D32*2 HO2 sensor connector.

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

Standard voltage (for Bank 1 sensor 1)

TESTER CONNECTION SPECIFIED CONDITION

Standard voltage (for Bank 2 sensor 1)

TESTER CONNECTION SPECIFIED CONDITION

NG : Go to step 4

Fig. 48: Identifying D31*1 Or D32*2 HO2 Sensor Connector Terminals

OK : Go to next step

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

a. Disconnect the D31*1 or D32*2 HO2 sensor connector.

b. Disconnect the D74 ECM connector.

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

Standard resistance (Check for open)

Tester Connection

Switch Condition Specified Condition

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

11 to 14 V

Tester Connection

Switch Condition Specified Condition

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

11 to 14 V

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

TESTER CONNECTION SPECIFIED CONDITION

Standard resistance (Check for short)

TESTER CONNECTION SPECIFIED CONDITION

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig. 49: Identifying D74 ECM Connector Terminals

OK : REPLACE ECM (See REMOVAL )

4. INSPECT FUSE (EFI NO. 2)

a. Remove the EFI NO. 2 fuse from the engine room junction block.

Tester Connection

Condition Specified Condition

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

Below 1 ohms

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

Below 1 ohms

Tester Connection

Condition Specified Condition

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

10 kohms or higher

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

10 kohms or higher

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra