Toyota Tundra. Manual — part 1232

malfunctions, is set, the ECM enters fail-safe mode. During fail-safe mode, the ECM cuts the current to the
throttle actuator, and the throttle valve is returned to a 6° throttle angle by the return spring. The ECM then
adjusts the engine output by controlling the fuel injection (intermittent fuel-cut) and ignition timing, in
accordance with the accelerator pedal opening angle, to allow the vehicle to continue running at a minimal
speed. If the accelerator pedal is depressed firmly and gently, the vehicle can be driven slowly. Fail-safe mode
continues until a pass condition is detected, and the ignition switch is then turned OFF.

WIRING DIAGRAM

Fig. 187: Throttle Actuator Control Motor Circuit - Wiring Diagram

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.



The throttle actuator current (Throttle Motor Current) and the throttle actuator duty ratio (Throttle Motor
Open Duty/Throttle Motor Close Duty) can be read using the Techstream. However, the ECM shuts off
the throttle actuator current when the ETCS malfunctions.

1. INSPECT THROTTLE BODY (RESISTANCE OF THROTTLE ACTUATOR)

a. Disconnect the D9 throttle body connector.

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

Standard resistance

TESTER CONNECTION SPECIFIED CONDITION

Tester Connection Condition Specified Condition

2 (M+) - 1 (M-)

20°C (68°F)

0.3 to 100 ohms

2008 Toyota Tundra

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

NG : REPLACE THROTTLE BODY (See REMOVAL )

Fig. 188: Identifying D9 Throttle Body Connector Terminals

OK : Go to next step.

2. CHECK HARNESS AND CONNECTOR (THROTTLE ACTUATOR - ECM)

a. Disconnect the D9 throttle body 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 SPECIFIED CONDITION

Standard resistance (Check for short)

TESTER CONNECTION SPECIFIED CONDITION

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

Tester Connection

Condition Specified Condition

D9-2 (M+) - D74-19 (M+) Always

Below 1 ohms

D9-1 (M-) - D74-18 (M-)

Always

Below 1 ohms

Tester Connection

Condition Specified Condition

D9-2 (M+) or D74-19 (M+) - Body ground Always

10 kohms or higher

D9-1 (M-) or D74-18 (M-) - Body ground

Always

10 kohms or higher

2008 Toyota Tundra

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

Fig. 189: Identifying D9 Throttle Body Connector & D74 ECM Connector Terminals

OK : Go to next step.

3. INSPECT THROTTLE BODY (VISUALLY CHECK THROTTLE VALVE)

a. Check for foreign objects between the throttle valve and the housing.

NG : REMOVE FOREIGN OBJECT AND CLEAN THROTTLE BODY

OK : Go to next step.

4. INSPECT THROTTLE VALVE

a. Check if the throttle valve opens and closes smoothly.

NG : REPLACE THROTTLE BODY (See REMOVAL )

OK : REPLACE ECM (See REMOVAL )

DTC P2111 THROTTLE ACTUATOR CONTROL SYSTEM - STUCK OPEN; DTC P2112
THROTTLE ACTUATOR CONTROL SYSTEM - STUCK CLOSED

SYSTEM DESCRIPTION

The throttle actuator is operated by the ECM, and opens and closes the throttle valve using gears. The opening
angle of the throttle valve is detected by the Throttle Position (TP) sensor, which is mounted on the throttle
body. The TP sensor provides feedback to the ECM. This feedback allows the ECM to appropriately control the
throttle actuator and monitor the throttle opening angle as the ECM responds to driver inputs.

2008 Toyota Tundra

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

HINT:

This ETCS (Electronic Throttle Control System) does not use a throttle cable.

DTC TROUBLE DETECTION CONDITION CHART

MONITOR DESCRIPTION

The ECM determines that there is a malfunction in the ETCS when the throttle valve remains at a fixed angle
despite a high drive current from the ECM. The ECM illuminates the MIL and sets a DTC. If the malfunction is
not repaired successfully, a DTC is set when the accelerator pedal is fully depressed and released quickly (to
fully open and close the throttle valve) after the engine is next started.

MONITOR STRATEGY

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

All:

TYPICAL ENABLING CONDITIONS

P2111 (Throttle actuator stuck open)

DTC No.

DTC Detection Condition

Trouble Area

P2111 ECM signals throttle actuator to close, but stuck (1 trip detection logic)



Throttle actuator



Throttle body



Throttle valve



ECM

P2112 ECM signals throttle actuator to open, but stuck (1 trip detection logic)



Throttle actuator



Throttle body



Throttle valve



ECM

Related DTCs

P2111: Throttle actuator stuck open
P2112: Throttle actuator stuck closed

Required Sensors/Components (Main)

Throttle actuator

Required Sensors/Components (Related)

-

Frequency of Operation

Continuous

Duration

0.5 seconds

MIL Operation

Immediate

Sequence of Operation

None

Monitor runs whenever following DTCs are not present

None

2008 Toyota Tundra

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