Clean away all paint and rust from your ground source. Connect E1 , E01 , and E02 securely to the chassis and engine block.
If you’re working on a Toyota with the 3S-FE engine (common in Camry, Celica, Curren and some RAV4/Carina models from the late 1980s through the early 2000s), having a clear ECU pinout makes diagnosing sensors, swapping ECUs, or building a wiring harness much easier. Below is a concise, practical blog-style overview you can use as a starting point. (This is a general guide — pin numbering and wire colors can vary by model year and market; always verify against the vehicle’s factory manual or the specific ECU label.)
IGT (Ignition Timing) and IGF (Ignition Confirmation). Multi-coil systems use IGT1, IGT2, etc..
Testing if a specific sensor (like the MAP or Oxygen sensor) is sending a signal to the ECU. 3s-fe ecu pinout pdf
When reading these diagrams, the following codes typically apply: L W R BR G GR Y AI responses may include mistakes. Learn more 3sfe 3sge Wiring Diagrams | PDF - Scribd
3S-FE 1997-2002 Engine Control - Free download as PDF File (.pdf) or read online for free. 3S-FE Wiring Diagram | PDF - Scribd
To help narrow down your wiring or documentation search, let me know the the engine came from, or the OEM part number on the ECU casing. I can also help you troubleshoot specific engine symptoms or guide you through a standalone ECU conversion . Share public link Clean away all paint and rust from your ground source
Monitors the exact position of internal engine components via the Crankshaft and Camshaft Position Sensors to fire the spark plugs accurately. Fuel Delivery:
Manages sensor inputs including the Crankshaft position sensor (NE+) , Camshaft position sensor (G+) , and Throttle position sensor (VTA) .
The signal sent back to the ECU to confirm a spark happened. Without this, the ECU will cut fuel for safety. 3. Fuel & Air Sensors Below is a concise, practical blog-style overview you
Turn the ignition off. Find the thickest white-red wire (BATT). It should have 12V constant. Find the thick brown or white-black wires (E01, E02). These are high-current grounds for injectors.
If your engine isn't running correctly, use a multimeter at the ECU harness: With the key ON, you should see 12V at +B .
OBD1 diagnostic communication pins. Shorting TE1 to E1 triggers the dashboard "Check Engine" light to flash fault codes. OX / OX1: Oxygen sensor signal monitoring air-fuel ratios.
If you cannot find a PDF, or you suspect your harness has been modified, you can reverse-engineer the pinout yourself. This is tedious but foolproof.
3S-FE 1997-2002 Engine Control - Free download as PDF File (.pdf) or read online for free. 3S-FE Wiring Diagram | PDF - Scribd
