Toyota Tundra. Manual — part 1172

HINT:



When any of these DTCs are set, check the throttle valve opening angle by entering the following menus:
Powertrain/Engine and ECT/Data List/ETCS/Throttle Position No.1 and Throttle Position No.2.



Throttle Position No.1 is the VTA1 signal, and Throttle Position No.2 is the VTA2 signal.

Reference (Normal Condition)

VOLTAGE REFERENCE

MONITOR DESCRIPTION

P0123

Output voltage of VTA1 4.535 V or more for 2 seconds when
accelerator pedal depressed (1 trip detection logic)



Open in VTA1 circuit



Open in E2 circuit



Short between VC and
VTA1 circuits



ECM

P0220

Output voltage of VTA2 quickly fluctuates beyond lower and
upper malfunction thresholds for 2 seconds when accelerator pedal
depressed (1 trip detection logic)



TP sensor (built into
throttle body)



ECM

P0222

Output voltage of VTA2 1.75 V or less for 2 seconds when
accelerator pedal depressed (1 trip detection logic)



TP sensor (built into
throttle body)



Short in VTA2 circuit



Open in VC circuit



ECM

P0223

Output voltage of VTA2 4.8 V or more, and VTA1 between 0.2 V
and 2.02 V for 2 seconds when accelerator pedal depressed (1 trip
detection logic)



TP sensor (built into
throttle body)



Open in VTA2 circuit



Open in E2 circuit



Short between VC and
VTA2 circuits



ECM

P2135

Either condition (a) or (b) met (1 trip detection logic)

a. Difference between output voltages of VTA1 and VTA2

0.02 V or less for 0.5 seconds or more

b. Output voltage of VTA1 0.2 V or less, and VTA2 1.75 V or

less, for 0.4 seconds or more



Short between VTA1
and VTA2 circuits



TP sensor (built into
throttle body)



ECM

Tester Display

Accelerator Pedal Fully Released

Accelerator Pedal Fully Depressed

Throttle Position No.1

0.5 to 1.1 V

3.3 to 4.9 V

Throttle Position No.2

2.1 to 3.1 V

4.6 to 5.0 V

2008 Toyota Tundra

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

The ECM uses the Throttle Position (TP) sensor to monitor the throttle valve opening angle. There are several
checks that the ECM performs to confirm the proper operation of the TP sensor.



A specific voltage difference is expected between the sensor terminals, VTA1 and VTA2, for each
throttle valve opening angle. If the difference between VTA1 and VTA2 is incorrect, the ECM interprets
this as a malfunction in the sensor, and sets a DTC.



VTA1 and VTA2 each have a specific voltage range. If VTA1 or VTA2 is outside the normal operating
range, the ECM interprets this as a malfunction in the sensor, and sets a DTC.



VTA1 and VTA2 should never be close to the same voltage level. If VTA1 is within 0.02 V of VTA2, the
ECM determines that there is a short circuit in the sensor, and sets a DTC.

If the malfunction is not repaired successfully, a DTC is set 10 seconds after the engine is next started.

MONITOR STRATEGY

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

Related DTCs

P0120: Throttle position sensor 1 range check (Fluctuating)
P0122: Throttle position sensor 1 range check (Low voltage)
P0123: Throttle position sensor 1 range check (High voltage)
P0220: Throttle position sensor 2 range check (Fluctuating)
P0222: Throttle position sensor 2 range check (Low voltage)
P0223: Throttle position sensor 2 range check (High voltage)
P2135: Throttle position sensor range check (Correlation)

Required Sensors/Components
(Main)

Throttle position sensor

Required Sensors/Components
(Related)

-

Frequency of Operation

Continuous

Duration

2 seconds: P0120, P0122, P0123, P0220, P0222 and P0223
(Accelerator pedal ON)
10 seconds: P0120, P0122, P0123, P0220, P0222 and P0223
(Accelerator pedal OFF)
0.5 seconds: P2135 Case 1
0.4 seconds: P2135 Case 2

MIL Operation

Immediate

Sequence of Operation

None

Monitor runs whenever following DTCs not present

None

Either of following conditions A or B met

-

A. Ignition switch ON

0.012 seconds or more

B. Electronic throttle actuator power

ON

2008 Toyota Tundra

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

P0120:

TYPICAL MALFUNCTION THRESHOLDS

P0122:

TYPICAL MALFUNCTION THRESHOLDS

P0123:

TYPICAL MALFUNCTION THRESHOLDS

P0220:

TYPICAL MALFUNCTION THRESHOLDS

P0222:

TYPICAL MALFUNCTION THRESHOLDS

P0223:

TYPICAL MALFUNCTION THRESHOLDS

P2135 Case 1:

TYPICAL MALFUNCTION THRESHOLDS

P2135 Case 2:

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

COMPONENT OPERATING RANGE

VTA1 voltage

0.2 V or less, or 4.535 V or more

VTA1 voltage

0.2 V or less

VTA1 voltage

4.535 V or more

VTA2 voltage

1.75 V or less, or 4.8 V or more

VTA2 voltage

1.75 V or less

VTA2 voltage when VTA1 0.2 V or more, and 2.02 V or less

4.8 V or more

Difference between VTA1 and VTA2 voltages

0.02 V or less

VTA1 voltage

0.2 V or less

VTA2 voltage

1.75 V or less

2008 Toyota Tundra

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

FAIL-SAFE

When any of these DTCs, as well as other DTCs relating to ETCS (Electronic Throttle Control System)
malfunctions, are 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 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. 75: Throttle/Pedal Position Sensor/Switch Wiring Diagram

INSPECTION PROCEDURE

HINT:



These DTCs relate to the Throttle Position (TP) sensor.



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

VTA1 voltage

0.69 to 4.05 V

VTA2 voltage

2.25 to 4.8 V

2008 Toyota Tundra

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