Accelerator Pedal Position Sensor
Accelerator Pedal Position Sensor at 1A Auto
What is a Accelerator Pedal Position Sensor and where is it Located?
The accelerator pedal position sensor - commonly abbreviated to APP sensor and also sometimes referred to as a gas pedal position sensor - is an electronic device used in cars with Electronic Throttle Control (ETC), or drive-by-wire, acceleration systems. It senses the position of the accelerator pedal (hence the name), and relays that information to the vehicle’s engine control module (ECM), or onboard computer. The computer then sends a signal to the throttle blade to open a valve that lets more air into the intake. This replaces the older, more straightforward mechanical linkage system in which the accelerator pedal pulled a metal cable that pulled the throttle body valve.
The accelerator pedal position sensor is attached to the pedal. The sensor inside of it is usually a Hall Effect sensor which determines the location of a moving part through a magnetic field and produces a change in charge based on a change in position. That charge is the information sent to the ECM, to tell the computer how hard you are pushing the pedal. Your accelerator assembly may actually include more than one of these devices so that there is a backup if one fails.
How do I Know if my Accelerator Pedal Position Sensor Needs to be Replaced?
The APP sensor can fail due to a problem with the wiring or a malfunction in the electronics of the sensor. These types of defects can occur over time through use. If the accelerator position sensor stops working then the ECM won’t have correct information about what kind of pressure you are putting on the gas pedal. This might make acceleration difficult or may lead to stalling.
If there are multiple sensors and they don’t agree, then the ECM will recognize that one of the accelerator sensors has failed and will put the engine into a failsafe, “limp home,” mode. You will also see the check engine light illuminate at this point. A diagnostic scan tool will show codes between P0220 and P0229 for accelerator sensor problems, as shown below.
Related OBDII codes
P0220 Throttle/Petal Position Sensor/Switch B Circuit Malfunction
P0221 Throttle/Petal Position Sensor/Switch B Circuit Range/Performance Problem
P0222 Throttle/Petal Position Sensor/Switch B Circuit Low Input
P0223 Throttle/Petal Position Sensor/Switch B Circuit High Input
P0224 Throttle/Petal Position Sensor/Switch B Circuit Intermittent
P0225 Throttle/Petal Position Sensor/Switch C Circuit Malfunction
P0226 Throttle/Petal Position Sensor/Switch C Circuit Range/Performance Problem
P0227 Throttle/Petal Position Sensor/Switch C Circuit Low Input
P0228 Throttle/Petal Position Sensor/Switch C Circuit High Input
P0229 Throttle/Petal Position Sensor/Switch C Circuit Intermittent
It is possible to check an APP sensor with a digital voltmeter. You will have to remove the accelerator pedal assembly from the vehicle, hook it up to the voltmeter and try working the pedal. The voltmeter will show smooth voltage changes if the accelerator sensor is working correctly.
Can I Replace an APP Sensor Myself?
At this point you may be thinking that this part is highly complicated, and in some ways it is, but it shouldn’t be difficult to replace. In some cases, you may be able to buy an entire new accelerator pedal assembly. In that case, you will have to disconnect the wiring harness, unbolt the old pedal assembly and install the new one. Otherwise, the process will be similar, except that you will have to remove the old sensor from the pedal assembly and swap in the new one.
Need a Replacement Accelerator Pedal Position Sensor?
Your vehicle’s APP sensor ultimately controls fuel flow in your car or truck. If it is malfunctioning, your vehicle may experience problems such as poor acceleration and reduced vehicle speed. Don’t let these problems happen to you – shop at 1A Auto for a high quality replacement! We carry aftermarket accelerator pedal sensors for many makes and models, and at great prices.
At 1A Auto, we make shopping for a replacement accelerator pedal position sensor for your car, truck, SUV or van easy - we're here to help you select the right part for your vehicle! Call our customer service toll free at 888-844-3393 if you have any questions about our sensors, warranty, compatibility or to purchase, or you can buy online.