4s-fe - Ecu Pinout __top__
He pulled the passenger kick panel. There it was: the 16-bit brain, a grey metal box stamped 89661-1A230 . Four plugs: A, B, C, and D. Sixty-two pins of silent judgment.
The information provided in this article is for general purposes only and should not be considered as a substitute for professional advice or guidance. Always consult the manufacturer's documentation and seek expert assistance when working with complex automotive systems.
Toyota ECU Wiring Instructions Guide | PDF | Computers - Scribd 4s-fe ecu pinout
Pin B13 (Green/Red) was the —Circuit Opening Relay control. When the ECU sees airflow (via the VAF meter, Pin B8, Yellow/Black), it grounds Pin B13, the fuel pump whirs, and the engine drinks.
| Pin | Wire Color | Function | Signal Type | Notes | |------|------------|-----------|-------------|-------| | A1 | White/Red | +B (Main EFI Relay) | 12V Battery | Power input to ECU | | A2 | White/Red | +B1 (EFI Relay 2) | 12V Battery | Secondary power | | A3 | Yellow | Injector #1 (Cyl 1) | Ground switched | ECU grounds to fire | | A4 | Yellow/Black | Injector #3 (Cyl 3) | Ground switched | | | A5 | Black/Orange | IACV (ISCV) – Open coil | Duty cycle | Idle Air Control Valve | | A6 | Blue/Red | IACV (ISCV) – Closed coil | Duty cycle | | | A7 | Black/Brown | ELS (Electrical Load) | 12V (active high) | A/C or headlight signal | | A8 | Yellow/Green | Injector #2 (Cyl 2) | Ground switched | | | A9 | Yellow/Blue | Injector #4 (Cyl 4) | Ground switched | | | A10 | Black/White | E01 (Power Ground) | Ground | Heavy ground for injectors | | A11 | Brown/White | E02 (Power Ground) | Ground | Same as E01 | | A12 | Black/Yellow | Check Engine Light (W) | Ground to illuminate | Bulb on dash (12V via cluster) | He pulled the passenger kick panel
Are you performing an or trying to diagnose a specific fault code with your 4S-FE?
With ignition ON, measure voltage between A1 and C11. You should see 11.5–12.5V. Sixty-two pins of silent judgment
For those performing an engine swap or building a custom harness, always verify the specific part number of your ECU. You can find detailed technical diagrams and shared community manuals on platforms like Scribd or specialized forums like ToyotaNation .