The single most critical piece of documentation for troubleshooting, engine swaps, or standalone management is the .
Pins TE1 and E1 are jumped at the diagnostic box to read "Check Engine" light codes for standard Toyota OBD-I systems. 4s-fe ecu pinout
This is the trigger signal sent to the igniter to fire the spark plugs. The single most critical piece of documentation for
While specific wire colors can vary between car models (e.g., a Mark II vs. a Carina), the following terminal codes are standard for Toyota ECUs of this era: Full Name / Function Switched Power +12V power from the EFI Main Relay when the ignition is ON. BATT Constant Battery Power Permanent +12V used to keep the ECU memory (DTCs) alive. E1 / E01 Main Ground The primary computer and power grounds for the ECU. E2 / E21 Sensor Ground While specific wire colors can vary between car models (e