| Sensor | ECU Pin | Signal Type | Wire Color (Typical) | | :--- | :--- | :--- | :--- | | | A10 (+) / A11 (-) | AC Sine Wave | Shielded Pair (Black/White) | | Camshaft Position (CMP) | A13 (+) / A14 (-) | Hall Effect | White / Black | | Rail Pressure Sensor | A16 (Signal) / A19 (Ground) / A20 (5V Ref) | 0.5-4.5V Analog | Green / Black / White | | Accelerator Pedal (APP1) | A33 (Signal) / A34 (Ground) / A35 (5V Ref) | Analog | Yellow / Blue / Red | | Intake Air Temp (IAT) | A22 (Signal) / A21 (Ground) | Analog | Brown / Black | | Coolant Temp (ECT) | A26 (Signal) / A25 (Ground) | Analog | Light Green / Black | | Atmospheric Pressure | A24 (Signal) / A23 (5V Ref) | Analog | Gray / White |
| Component | ECU Pin | Action | | :--- | :--- | :--- | | | A3 (+) / A4 (-) | Regulates fuel into the high-pressure pump | | Injector #1 | C1 (High) / C2 (Low) | High-side / Low-side driver | | Injector #2 | C3 / C4 | High-side / Low-side driver | | Injector #3 | C5 / C6 | High-side / Low-side driver | | Injector #4 | C7 / C8 | High-side / Low-side driver | | Main Relay Control | A2 | Sends ground to turn on the main relay | | Check Engine Light (MIL) | A9 | Switched ground (illuminates the light) | isuzu 4hl1-1 ecu pinout
Before chasing sensor signals, ensure the ECU is alive. | Sensor | ECU Pin | Signal Type