Diagnosis & Repair

WARNING: This page is about a different car, the 2003 Toyota MR2. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Using Toyota hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.

For diagnosis and repair procedure with Toyota Hand-held tester or an Enhanced OBD II scan tool, see Fig 1-Fig 6 .

For diagnosis and repair procedure with OBD II scan tool (Non Enhanced), see Fig 7-Fig 12 .

For fuel injector driver circuit wiring diagram, see Fig 13. For location of emission related components, see Figure.

For ECM location, see Figure. For ECM connector terminal view, see Figure.

To identify circuits referenced in testing, see ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. For vacuum or EVAP hose routing, see VACUUM DIAGRAMS article. For testing of systems or components, see BASIC DIAGNOSTIC PROCEDURES - 4-CYLINDER article or SYSTEM & COMPONENT TESTING - 4-CYLINDER article. For adjustments, see ON-VEHICLE ADJUSTMENTS - 4-CYLINDER article. For removal and installation of components, see REMOVAL & INSTALLATION - 4-CYLINDER article.

Fig 1: DTCs P0300 & P0301-P0304 Diagnostic Procedure Using Hand Held Tester (Steps 1-4)