Diagnosis & Repair
For wiring diagram of Corolla model, see Fig 1. For wiring diagram of Matrix (1ZZ-FE engine) model, see Fig 2. For wiring diagram of Matrix (2ZZ-GE engine) model, see Fig 3. For diagnosis and repair, see Fig 4-Fig 7. For testing of components, see SYSTEM & COMPONENT TESTING - 4-CYLINDER article. For removal and installation of components, see REMOVAL & INSTALLATION - 4-CYLINDER article. To check ECM inputs and outputs, see PIN VOLTAGE CHARTS article. To identify circuits referenced in testing, See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.