The 1KZ-TE system uses a for diagnostics. The procedure to read fault codes is straightforward and requires only a jumper wire:

Connects to crucial sensors like MAP, Throttle Position (TPS), and Coolant Temp.

Websites like ToyoDIY , PradoPoint , or HiluxSurf.co.uk frequently host high-resolution pinout images specific to different ECU part numbers (e.g., 89661-xxxxx).

KZN165 Hilux, late-model KZN185 Surf, and 120-series Prado.

To work safely and accurately on a 1KZ-TE, having the correct documentation is non-negotiable.

The physical layout of your 1KZ-TE ECU is important to identify before diving into pin assignments.

: This is the "Electronic" version. While it is often described as "old school," its engine management system is relatively sophisticated. It features an electronic injection pump controlled by the ECU via a Spill Control Valve (SPV) and various sensors. The "E" makes all the difference. This version requires a fully intact engine harness, a functioning ECU, and a correct wiring configuration to run. Most of the pinout discussions revolve around this specific variant.

Below is a comprehensive, structured reference for the Toyota 1KZ-TE / 1KZ-VE engine control unit (ECU) pinout. This covers common ECU connector layouts, typical pin functions, wiring colors and signal descriptions used in many Toyota models equipped with the 1KZ engine family (e.g., Hilux, HiAce, Prado, TownAce). Vehicle model years and regional wiring variations exist — use this as a general guide and verify against the vehicle’s factory service manual and wiring diagrams before testing or modifying.

Ground for injectors/actuators (high current). E1 (Ground): Logic ground for sensors. 2. Sensor Inputs

: Because the 1KZ-TE relies on an electronic injection pump, it responds well to aftermarket piggyback ECUs, such as the Unichip Uni-X. A piggyback ECU intercepts signals (often the boost pressure sensor and SPV wires) to modify fuel and timing, offering safer power gains than a mechanical pump conversion.

Pins like +B , +B1 , and E1/E01 for main battery power and grounding.

If the terminal is triggered, common codes include: Code 13 : No Crankshaft Position Sensor signal. Code 14 / 15 : Igniter circuit malfunctions (IGT). Code 42 : Vehicle Speed Sensor (SP1) signal issue.

: This code often indicates an open or short in the circuit between the ECU and the injection pump correction unit located directly on the injection pump. Because the pump is exposed to high vibration and heat, the wires inside the plastic connector housing frequently crack. Repairing the wiring harness or replacing the correction unit usually resolves the code.