The square 17-pin or 23-pin check connector near the fuse box can be used for diagnostics:
| Pin | Function | |-----|-----------| | TE1 | Connect to E1 to enter diagnostic mode | | TE2 | Test mode (stored codes) | | E1 | Ground | | VF1 | Air fuel ratio / injection feedback | | T | Tachometer signal | | +B | Battery voltage | | OP | Shift position (A/T) | 1kz ecu pinout
To read blink codes: Jump TE1 to E1 → Turn ignition ON → Read MIL (check engine light). The square 17-pin or 23-pin check connector near
| Pin | Wire Color | Signal Name | Function | Voltage / Signal | | :--- | :--- | :--- | :--- | :--- | | A1 | White/Red | +B1 | ECU Main Relay Power (Constant 12V from relay) | 12V (Key ON) | | A2 | Black/Orange | E01 | Power Ground (Injector driver return) | 0V | | A3 | Yellow/Black | #10 | Injector Driver – Cylinder 1 | Pulse (Battery voltage spike) | | A4 | Yellow | #20 | Injector Driver – Cylinder 2 | Pulse | | A5 | Light Green | #30 | Injector Driver – Cylinder 3 | Pulse | | A6 | White/Black | E02 | Power Ground (Sensor return) | 0V | | A7 | N/A | N/C | Not Connected | - | | A8 | Blue/Red | SCV+ | Spill Control Valve (+) (Fuel quantity) | PWM (0-12V pulses) | | A9 | Blue/Yellow | SCV- | Spill Control Valve (-) (Fuel quantity) | PWM (0-12V pulses) | | A10 | Yellow/Red | MREL | Main Relay Control (ECU switches relay ground) | 12V (Key ON) | | A11 | Red/White | +B | Constant ECU Backup Power (Memory) | 12V (Constant) | | A12 | White/Blue | IGSW | Ignition Switch Signal | 12V (Key ON) | | A13 | Blue/White | Stop L | Brake Pedal Signal (for idle-up logic) | 0V (Brake off) / 12V (Brake on) | | A14 | Black/White | E03 | Sensor Ground (ECU internal) | 0V | | A15 | Brown | #40 | Injector Driver – Cylinder 4 | Pulse | | A16 | Red | VCV+ | Timing Control Valve (+) | PWM | | A17 | Light Green/Black | VCV- | Timing Control Valve (-) | PWM | | A18 | Blue/Black | EDU | EDIC (Fuel cut solenoid – early models) | 12V (Run) / 0V (Stop) | | A19 | Black/Red | E04 | Shield Ground (for sensor cables) | 0V | | A20 | N/A | N/C | Not Connected | - | | A21 | N/A | N/C | Not Connected | - | | A22 | Black/Yellow | EO1 | Power Ground (High current) | 0V | | Pin | Wire Color | Signal Name
Before you start probing wires, identify your ECU part number. While the pinouts are largely consistent across the 1KZ-TE range, there are slight variations between automatic and manual transmissions, and early vs. late models.
| Pin | Wire Color | Function | Electrical Spec | |------|-------------|-------------------------------|------------------| | A1 | White/Red | Battery +12V (constant) | 11-14V | | A2 | White/Black | Main relay (IG SW) | 11-14V when ignition ON | | A3 | Black/White | ECU Ground (power ground) | <0.5 ohms to battery negative | | A4 | Black | Sensor ground (analog) | 0V reference | | A10 | Yellow/Black | Injection pump – timing control valve | 0-12V (PWM signal) | | A11 | Blue/Red | Injection pump – spill valve | 0-8V (PWM) | | A14 | Red/Black | Stop solenoid (fuel cut) | 12V when running; 0V off | | A20 | Green/White | Glow plug relay control | 12V during pre-heat | | A24 | Black/Orange | Engine control relay (ECU main) | 12V ignition ON |
Common Failure: Pin A3 (ground) corrodes. Symptoms include random stalling and low injection pump pressure.