Throttle Position Sensor (Hard-Wired)

The Throttle Position Sensor (TPS) is used by the TCM to help determine shift points and shift quality Additionally, the TPS output is spliced to the PCM for fuel control. The PCM provides a 5 volt supply and ground for the sensor. Target idle speed is compared against actual engine speed to determine the learned TPS value for closed throttle idle. This is done to correct for differences in system voltage and sensor tolerances.

If the TCM detects a faulty TPS signal, it provides continued operation of the transaxle by substituting a throttle position default value near 1/3 full open, or 25 degrees (for 1997 and earlier vehicles). In 1998 relative throttle begins. This substitution value results in upshifts and downshifts that are vehicle speed dependent.

NOTE: Refer to TSB 18-13-94 if erratic shifting is evident.