: Identify pins that show constant 12V even when the ignition is off.

Isuzu 4HL1 ECU pinout and full wiring diagrams are primarily found in the

From technical diagnostics of the 4HL1 Transtron ECU, common pin assignments often include:

While similar to the 4HK1, specific 4HL1 pin assignments for components like the SCV (Suction Control Valve), injectors, and various sensors are listed in these technical guides. Key Connector Pin Assignments (Sample)

on Scribd contains the complete Section 1A, covering the engine control system, diagnostics, and full wiring schematics. Circuit Diagrams: