Toyota 89661 Ecu Pinout Online

Always look at the physical connectors on your ECU before using any online pinout. Count the pins and compare with known diagrams.

💡 Always measure voltage at the ECU pins while the engine is cranking. A pinout might show 12V at +B , but if that drops below 9V during cranking, the ECU may reboot or fail to fire the injectors.

The "89661" number is just the beginning. The five digits that follow determine the specific engine, transmission, and market (JDM vs. USDM) the unit was designed for. Typically Corolla or Levin (4A-GE engines). 89661-22xxx: Often Chaser or Mark II (1JZ-GTE engines). 89661-30xxx: Commonly GS300 or Aristo (2JZ engines). 89661-17xxx: Usually MR2 (3S-GTE engines). toyota 89661 ecu pinout

Reviewing the requires understanding that "89661" is the root part number for nearly all Toyota/Lexus Engine Control Units (ECUs) . Because this number covers decades of different engines—from the 22RE to modern VVT-i systems—the pinout depends entirely on the specific suffix (e.g., 89661-35441) . Critical Review of Finding & Using Pinouts Toyota Lexus ECU 89661-50102 repair

Look at the label on the ECU. Example: 89661-60A70 (2006 RAV4). If the label is gone, check the original vehicle’s VIN sticker under the hood or door jamb. Always look at the physical connectors on your

Avoid using "test lights" on signal wires as they can draw too much current and fry internal ECU drivers.

Note: Pin A1 must have constant 12V even with engine off. Loss of this pin erases adaptive fuel trims and causes rough idle. A pinout might show 12V at +B ,

| Resource | Best for | |----------|-----------| | – paid, official | Exact OEM diagrams | | eBay / ECU repair photos – search "89661-xxxxx pinout" | Often sellers include pinout photos | | Forum threads – ToyotaNation, SupraForums, MR2OC | Community-contributed pinouts | | ECM repair manuals – online shops like ECU Testing, AutoHex | Professional pinout lists | | AlldataDIY / Mitchell1 | Subscription but reliable |

Because the "89661" part number is a generic prefix used across dozens of engines (like the 1JZ, 2JZ, and 3S-GTE), pinpointing your specific configuration is the first step toward a successful project. Identifying Your Specific 89661 ECU

If you provide the number, I can help identify the likely engine and connector layout, and direct you to the most reliable pinout source for that specific ECU.