Circuit Description

The TP sensor is a variable resistor that monitors throttle opening. The ECM determines vehicle driving condition and adjusts air/fuel mixture accordingly. DTC is set when ECM consistently detects less than .1 volt on VTA circuit. DTC will also set if ECM consistently detects 4.9 volts or more on VTA circuit. Possible causes are:

TP sensor open or short circuit.
TP sensor.
ECM.

NOTE: If DTCs P0110, P0115 and P0120 are output together, inspect ECM terminal E2 (ground) circuit. Repair as necessary. See appropriate wiring diagram in WIRING DIAGRAMS article.