RJK

2007 Suburban LTZ
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Has anyone changed out the Throttle position sensor? From what I’m told it is not under hood but on the gas pedal inside the cabin. The check engine light is on showing the code for the TPS, it is the entire gas pedal assembly any one change this out and if so how difficult and any special tools needed.
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Thanks

in2pro

check with your dealer this item may be covered under your 5yr 100k power train

RJK

After looking into this a bit more, it could be my TB is dirty setting off the code. I think I will try cleaning it and see what happens. I know I clean the TB on my Grand Cherokee and it always has crap in it carbon I think.

in2pro

Always an excellent place to start, with the easy free* things....

ssnellinger

Throttle position sensor is part of the throttle body. I just replaced mine. You can't just replace the sensor on the 07, you have to replace the entire throttle body.

in2pro

They just can't make it easy any more can they......

The throttle actuator control (TAC) system uses two throttle position (TP) sensors to monitor the throttle position. The TP sensors 1 and 2 are located within the throttle body assembly. Each sensor has the following circuits:

• A 5-volt reference circuit

• A low reference circuit

• A signal circuit


2007 Chevrolet Tahoe - 2WD | Avalanche, Escalade, Suburban, Tahoe, Yukon (VIN C/K) Service Manual | Document ID: 1672049
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Throttle Actuator Control (TAC) System Description
Purpose
The throttle actuator control (TAC) system delivers improved throttle response and greater reliability and eliminates the need for mechanical cable. The TAC system performs the following functions:

• Accelerator pedal position sensing

• Throttle positioning to meet driver and engine demands

• Throttle position sensing

• Internal diagnostics

• Cruise control functions

• Manage TAC electrical power consumption

The TAC system includes the following components:

• The accelerator pedal position (APP) sensors

• The throttle body assembly

• The engine control module (ECM)

Accelerator Pedal Position (APP) Sensor
The accelerator pedal contains 2 individual APP sensors within the assembly. The Accelerator Pedal Position (APP) sensors 1 and 2 are potentiometer type sensors each with 3 circuits:

• A 5-volt reference circuit

• A low reference circuit

• A signal circuit

The APP sensors are used to determine the pedal angle. The engine control module (ECM) provides each APP sensor a 5-volt reference circuit and a low reference circuit. The APP sensors provide the ECM with signal voltage proportional to the pedal movement. The APP sensor 1 signal voltage at rest position is less than 1 volt and increases to above 4 volts as the pedal is actuated. The APP sensor 2 signal voltage at rest position is near 0.5 volt and increases to more than 2 volts as the pedal is actuated.

Throttle Body Assembly
The throttle assembly contains the following components:

• The throttle blade

• The throttle actuator motor

• The throttle position (TP) sensor 1 and 2

The throttle body functions similar to a conventional throttle body with the following exceptions:

• An electric motor opens and closes the throttle valve.

• The throttle blade is spring loaded in both directions and the default position is slightly open.

• There are 2 individual TP sensors within the throttle body assembly.

The TP sensors are used to determine the throttle plate angle. The TP sensors provide the engine control module (ECM) with a signal voltage proportional to throttle plate movement. The TP sensor 1 signal voltage at closed throttle is above 4 volts and decreases as the throttle plate is opened. The TP sensor 2 signal voltage at closed throttle is below 1 volt and increases as the throttle plate is opened.

Engine Control Module
The engine control module (ECM) is the control center for the throttle actuator control (TAC) system. The ECM determines the drivers intent and then calculates the appropriate throttle response. The ECM achieves throttle positioning by providing a pulse width modulated voltage to the TAC motor.

Modes of Operation
Normal Mode
During the operation of the throttle actuator control (TAC) system, several modes or functions are considered normal. The following modes may be entered during normal operation:

• Minimum pedal value--At key-up the engine control module (ECM) updates the learned minimum pedal value.

• Minimum throttle position (TP) values--At key-up the ECM updates the learned minimum TP value. In order to learn the minimum TP value, the throttle blade is moved to the closed position.

• Ice break mode--If the throttle is not able to reach a predetermined minimum throttle position, the ice break mode is entered. During the ice break mode, the ECM commands the maximum pulse width several times to the throttle actuator motor in the closing direction.

• Battery saver mode--After a predetermined time without engine RPM, the ECM commands the battery saver mode. During the battery saver mode, the TAC module removes the voltage from the motor control circuits, which removes the current draw used to maintain the idle position and allows the throttle to return to the spring loaded default position.

Reduced Engine Power Mode
When the ECM detects a condition with the TAC system, the ECM may enter a reduced engine power mode. Reduced engine power may cause one or more of the following conditions:

• Acceleration limiting--The ECM will continue to use the accelerator pedal for throttle control; however, the vehicle acceleration is limited.

• Limited throttle mode--The ECM will continue to use the accelerator pedal for throttle control; however, the maximum throttle opening is limited.

• Throttle default mode--The ECM will turn off the throttle actuator motor and the throttle will return to the spring loaded default position.

• Forced idle mode--The ECM will perform the following actions:

- Limit engine speed to idle by positioning the throttle position, or by controlling the fuel and spark if the throttle is turned off.

- Ignore the accelerator pedal input.

• Engine shutdown mode--The ECM will disable fuel and de-energize the throttle actuator.
© 2011 General Motors Corporation. All rights reserved.

RJK

2007 LTZ

I am currently getting these 2 messages
1. Service Stabilitrak
2. Service Traction Control

Could on of the TB sensors be the cause of these functions turning off? I read some where they may be related?
I was thinking wheel speed senor is the problem.

I am leaving Sat. Morning for a trip 170 miles each way and I know I am not getting to the dealer before I leave Sat. morning. Will the above 2 issues cause problems? I understand I do not have the aid of 1 and 2 listed above while driving.

Any idea?
Thanks

ssnellinger

I had the identical info. come up on my DIC. I put a scan tool on and the code came up to replace the throttle position sensor. This is part of the throttle body, so the entire assembly had to be replaced. GM has obviously had a problem with this because none of my local dealers had them. They informed me that the new units were released Feb. 11 and the y are starting to come in. The throttle body can be replaced in less than 30 min.

RJK

Maybe I should go to Autozone pull the codes and if it is TB have it replaces under my powertrain warranty. I had the TB code about a month ago I cleaned the TB and it went away now the traction control and stabilitrak out giving me warnings I bet it is all related and I need to replace my TB.

I have no check engine light just the lights for traction control and stabilitrak will I get codes from these with a scan tool?

Thanks

Chevrolet Customer Service

RJK, have you gotten this issue resolved yet or does the problem persist? I would like to do what I can for you.

Jeff Morris, Chevrolet Customer Service