Voltage of APP2 signal should be exactly half of APP1 signal ±0.1V.
Wakes up the microprocessors when the key is turned to the "ON" position. isuzu 4hl1 ecu pinout
The 45-pin ECU connector has additional pins for features like cruise control, transmission control, and more. Voltage of APP2 signal should be exactly half
If you are diagnosing a specific issue, sharing the or the exact fault codes you are seeing would help narrow down the problem. Do you need help identifying a specific wire color , or are you working on an engine swap project ? Share public link If you are diagnosing a specific issue, sharing
Found on legacy models for direct diagnostic scanner communication. Step-by-Step Guide to Reading the Pinout Diagram
| Pin No. | Wire Color | Function | Notes | |---------|------------|----------|-------| | A10 | Green/Black | Rail Pressure Sensor (Signal) | 0.5V (0 bar) to 4.5V (1800 bar) | | A11 | Black/Yellow | Rail Pressure Sensor (Ground) | Shared with sensor ground | | A12 | Red/Blue | Rail Pressure Sensor (+5V) | From A32 reference | | B16 | White/Black | Suction Control Valve (SCV) (+) | PWM output to lift pump on HP3 pump | | B17 | Black/Red | Suction Control Valve (SCV) (-) | - | | B18 | Yellow/Green | Rail Pressure Regulator (PCV) (+) | Normal: 10–30% duty cycle | | B19 | Yellow/Black | Rail Pressure Regulator (PCV) (-) | - |
If you are dealing with a "No Start" condition or a specific diagnostic trouble code (DTC) like or P0335 (Crankshaft Position Sensor Circuit Fault) , use your pinout guide to systematically isolate the issue. Step 1: Check Power and Ground Integrity