Do not assume pin positions by color coding. Toyota changes wire colors between model years and even between sedan vs. wagon versions of the same car.
Constant 12V from the battery (maintains ECU memory/codes). toyota 89661 ecu pinout
Below are the most common pin abbreviations and terminal layouts used across the 89661 series: Common ECU Pin Abbreviations Do not assume pin positions by color coding
: 5V reference voltage output for sensors like the TPS. follow these standard procedures:
: Common issues like leaking capacitors in older 89661 modules (frequent in 1990s models like the Lexus LS400 or Toyota Celsior) require opening the unit and understanding its internal layout. Common Toyota 89661 Variations
When diagnosing a 89661 ECU, follow these standard procedures: