1kz Ecu Pinout May 2026

| Model | Stop Solenoid (A14) | TPS Signal (B4) | Crank Sensor (B1) | |-------------------|-------------------|-------------------|---------------------| | KZJ70 Prado | Red/Black | Yellow/Green | Red/Blue | | KZJ90 Prado | Red/White | Yellow/Black | Blue/Black | | Hilux Surf | Red/Black | Green/Yellow | Red/Blue | | Hiace (Van) | Black/Yellow | Yellow/Green | Light Green/Black |

Always confirm pin position by number, not color alone. The pinout’s position is consistent; the wire color is a guide. If you’re building an off-road buggy or custom 4×4, you might need to depin the ECU connectors.

Pin A3 (ground) corrodes. Symptoms include random stalling and low injection pump pressure. Connector B – Sensor Inputs (22P) | Pin | Wire Color | Sensor | Signal (Key ON) | |------|-------------|---------------------------|------------------| | B1 | Red/Blue | Crankshaft position (NE) | AC 0.5-1.0V (cranking) | | B2 | White/Blue | Camshaft position (G signal) | AC 0.5-1.0V | | B4 | Yellow/Green | Throttle position sensor (VTA) | 0.5V idle – 4.5V WOT | | B6 | Brown/White | Engine coolant temp (THW) | 2.5V cold – 0.2V hot | | B7 | Green/Black | Intake air temp (THA) | 3.0V cold – 1.0V hot | | B9 | Pink/Blue | Boost pressure sensor (PIM) | 1.0V at 0 psi – 3.5V at 15 psi | | B13 | Violet/White | Vehicle speed sensor (SPD) | 0-5V pulse (AC) | | B18 | Blue/Yellow | Neutral start switch (NSW) | 0V in Park/Neutral; 12V in gear | | B20 | Gray | EGR lift sensor | 0.5-4.5V | 1kz ecu pinout

Understanding the Electronic Control Unit (ECU) pinout diagram is not just for wiring nerds. It is the roadmap to troubleshooting injection pump timing, sensor failures, and communication issues. In this guide, we will dissect every pin, its function, voltage readings, and common failure points. The 1KZ-TE uses a distributor-type injection pump (Bosch VE style) controlled electronically by a Toyota ECU (part numbers often starting with 89661-3xxxx). Unlike fully mechanical diesels, this engine relies on a Throttle Position Sensor (TPS), coolant temperature sensor, boost sensor, and a crankshaft position sensor to determine fuel delivery.

No start but cranking? Check Pin B1 (crank sensor) resistance should be 1.6–2.1 kΩ. If open, the ECU never fires the injectors. Connector C – Outputs & Communications (16P) | Pin | Wire Color | Function | Notes | |------|-------------|---------------------------|------------------------------| | C1 | Black | TC terminal (check engine light) | Switched ground – illuminates when fault exists | | C2 | White | Tachometer output | 12V square wave (diesel tach) | | C3 | Green | AC idle-up request | 12V when AC compressor on | | C5 | Orange | Diagnostic (SIL) | 9600 baud for Toyota scanner | | C6 | Blue/Red | EGR vacuum switching valve (VSV) | 12V control | | C9 | Yellow | Immobilizer communication (if equipped) | Serial data to transponder amp | | C10 | Brown/Red | Fuel heater relay | 12V below 5°C | | C12 | Pink | Idle-up VSV for power steering | 12V at steering load | | Model | Stop Solenoid (A14) | TPS

Always start with the pinout. Never throw parts at a diesel ECU until you verify voltage, ground, and signal at the pins. Part 8: Wire Color Variations (Prado vs. Hiace vs. Surf) Toyota changed wire colors slightly by model:

The Toyota 1KZ-TE is one of the most beloved diesel engines ever produced. Found in legendary vehicles like the Land Cruiser Prado (KZJ70, KZJ90), Hilux Surf, and Hiace van, this 3.0-liter turbo-diesel is known for its reliability—until an electrical gremlin appears. Pin A3 (ground) corrodes

When the engine starts cutting out under load, refuses to start when hot, or logs a hard-to-read check engine light, the first place a professional mechanic turns is the .