SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSTOYOTA2004MATRIX XR, FWD, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 79 (ENGINE CONTROLS - SELF-DIAGNOSTICS)DIAGNOSTIC TESTSDTC P1120: ACCELERATOR PEDAL POSITION SENSOR CIRCUIT MALFUNCTIONCIRCUIT DESCRIPTION
2004 Toyota Matrix XR, FWD, Standard

Circuit Description

2004 Toyota Matrix XR, FWD, StandardSECTION Circuit Description
WARNING: This page is about a different car, the 2002 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.

The accelerator pedal position sensor is a 2 variable resistor sensor that monitors throttle opening and accelerator pedal position sensor malfunction. Accelerator pedal position sensor determines vehicle accelerator pedal position. ECM controls throttle motor based on signal from accelerator pedal position sensor. If DTC P1120 is set, ECM shuts down power to throttle control motor and electromagnetic clutch.

DTC P1120 is set when ECM consistently detects .2 volt or less, or 4.8 volts or more from VPA circuit, or .5 volt or less from VPA2 circuit for .5 second. DTC P1120 is also set when ECM consistently detects .2 volt or more and 3.45 volts or less from VPA circuit, and 4.8 volts or more from VPA2 circuit for .5 second.

DTC P1120 is also set when ECM consistently detects .02 volt or less from VPA/VPA2 circuit for .5 second. DTC P1120 is also set when ECM consistently detects .2 volt or less from VPA and .5 volt or less from VPA2 circuit for 2 seconds. Possible causes are:

  • Open or short in accelerator pedal position sensor circuit.
  • Faulty accelerator pedal position sensor.
  • Faulty ECM.

NOTE: If DTCs P0110, P0115, P0120, P0450 and P1120 are output together, inspect ECM ground circuit(s) for an open. Repair as necessary. See WIRING DIAGRAMS article.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.