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 |
Bad injection pump ($2,000 repair quote).
| 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 | 1kz ecu pinout
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 .
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. Pin A3 (ground) corrodes
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:
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. | Model | Stop Solenoid (A14) | TPS
Terminal release tool (small flathead), replacement pins (from Toyota or Ballenger Motorsports), and the official Toyota Electrical Wiring Diagram (EWD).