Toyota 89661 Ecu Pinout ((top)) <Secure | Checklist>

If you are running an aftermarket igniter or a bypassed circuit, a missing IGF signal will cause the ECU to shut down the injectors after the first engine revolution. Engine Starts, Then Immediately Dies

Look at the base of the plug pins on both sides of the circuit board. Toyota routinely prints the labels ( +B , BATT , E1 , etc.) directly on the board.

Common setups include 34-22-16-28 pin combinations.

Splicing sensor grounds ( E2 ) into chassis grounds ( E1 ) introduces electrical noise from the alternator and starter motor into the sensor lines. This causes erratic idle behaviors, inaccurate coolant temperature readings, and false oxygen sensor codes. Keep sensor grounds completely isolated on their dedicated pins. Pro-Tips for Wiring and Custom Swaps toyota 89661 ecu pinout

Camshaft position sensor signals used to determine cylinder sequencing. VTA / VTA2: Throttle Position Sensor (TPS) signal voltage.

Oxygen sensor signal and oxygen sensor heater control. Step-by-Step Guide to Finding Your Specific 89661 Pinout

This is a technical request regarding the series ECU (Engine Control Unit). The number 89661 is Toyota’s part number prefix for engine ECUs, but it is not a single pinout . It covers hundreds of different models (Camry, Corolla, Land Cruiser, Lexus, etc.) across OBD-I, OBD-II, JDM, and USDM variants. If you are running an aftermarket igniter or

Attach +B , +B1 , and IGSW to the positive 12V terminal through a toggle switch. This switch acts as your vehicle's ignition key.

1JZ-GTE VVTi, 2JZ-GTE VVTi, 1UZ-FE (VVTi variants), 2AZ-FE.

: Ignition Timing signals sent to the igniter/coils to trigger a spark. Common setups include 34-22-16-28 pin combinations

Often uses 31-pin, 24-pin, and 17-pin layouts housed in white plastic plugs.

Toyota ECUs generally fall into three design eras. Identifying your era helps narrow down the correct pinout map. The Yellow-Plug Era (Late 1980s – Late 1990s) : 4A-GE, 3S-GTE, 1UZ-FE (early), 1JZ-GTE.

Despite differences, most 89661 ECUs share a logical pin grouping. Below is a typical arrangement for a 4-connector 89661 ECU (Connectors A, B, C, D).