Diagnosis & Repair

WARNING: This page is about a different car, the 2003 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.

Read freeze frame data using the hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when a malfunction is detected. After confirming DTC P2121, use the hand-held tester or the OBD II scan tool to confirm the accelerator pedal position sensor output voltage. See Figure.

For diagnosis and repair with Toyota Hand-held tester or an Enhanced OBD II scan tool, see Fig 1. For diagnosis and repair with generic OBD II scan tool (Non Enhanced), see Fig 2.

For APP sensor wiring diagram, see Figure. For ECM location, see Figure. For ECM connector view, see Figure. For testing of systems or components, see BASIC DIAGNOSTIC PROCEDURES - V6 & V8 article or SYSTEM & COMPONENT TESTING - V6 & V8 article. For removal and installation of components, see REMOVAL & INSTALLATION - V6 & V8 article.

Fig 1: DTC P2121 Diagnostic Procedure Using Hand-Held Tester

Fig 2: DTC P2121 Diagnostic Procedure Using OBD II Scan Tool