Circuit Description

The Throttle Position (TP) sensor is a potentiometer mounted on side of throttle body. TP sensor voltage signal changes relative to throttle blade angle. TP sensor uses a 5-volt reference, a ground and a signal circuit. TP sensor signal voltage should be about 0.6 volt at idle and 4 volts or more at wide open throttle. PCM compares actual throttle position from TP sensor to a predicted throttle position value. The predicted value is calculated from engine speed and other inputs. If PCM detects predicted throttle position is less than actual TP sensor value, DTC will set.

DTC will set when following conditions are present:

• No MAP or TP sensor DTCs set.
• Engine running for more than 10 seconds.
• Engine coolant temperature is greater than 32°F (0°C).
• IAC between 0-255 counts.
• MAP less than 55 kPa or greater than 65 kPa.
• MAP steady.
• Predicted throttle angle is less than actual throttle angle.
• Conditions met for 20 seconds.