Circuit Description

Throttle Position (TP) sensor is a potentiometer whose resistance changes along with throttle valve position. PCM provides a 5-volt reference voltage to TP sensor. PCM reads voltage across sensor and converts it into a reference for throttle position. When TP sensor resistance decreases, throttle valve opening is increasing to Wide Open Throttle (WOT) and voltage being monitored at PCM increases. When TP sensor resistance increases, throttle valve opening is decreasing to idle and voltage being monitored at PCM decreases.

When DTC sets, MIL will illuminate after 2 consecutive ignition cycles in which diagnostic runs with active fault. PCM will record operating conditions at time of diagnostic failure and store information in FREEZE FRAME/FAILURE RECORDS data buffer.