AEM 30-71XX Infinity Stand-Alone Programmable Engine Mangement System Full Manual - Manual (Page 304)

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© 2014 AEM Performance Electronics
Infinity User Manual
PPS (Pedal Position Sensor)
For safety, modern cars use electronic throttle control (ETC) or sometime called drive-by-wire
(DBW) throttle bodies. The butterfly valve is no longer directly controlled by the throttle pedal via a
simple cable. The ECU relies on inputs from the pedal position sensors and other inputs from
various sensors. An output is then provided to control the DBW motor.
The PPS is similar to a TPS as they are both potentiometers. However, instead of mounted on
the butterfly valve, PPS are mounted on the throttle pedal. Pushing in the "gas" effectively rotates
the pedal and varies the resistance. Consequently, the voltage returned to the ECU is a function
of that resistance. The rate of change is measured to determine whether a vehicle is accelerating
or decelerating. Based on this rate of change, the proper amount of fuel is either added or
subtracted from the ECU calibration to achieve the proper amount of fuel for the operating
condition.