Code P026, Shorted Throttle Position Switch Circuit: Notes

Throttle position switch is part of ISC motor assembly. PCM provides a 5-volt reference on circuit No. 427. When throttle lever contacts ISC plunger, throttle position switch closes. When throttle position switch is closed, input voltage is low. Code P026 sets when PCM sees a TP sensor signal between 20 and 75 degrees (accelerator applied) but throttle position switch remains closed.