2003 Infiniti M45FACTORY OEM SERVICE PROCEDURE

Engine Control Module

The Engine Control Module (ECM) consists of a microcomputer, connectors and wiring for voltage signal input/output and power supply. The unit is not serviceable and should not be opened. The ECM contains memory and logic circuits, enabling it to interpret sensor inputs and control various engine systems. To locate ECM, see ECM LOCATIONSΒ  table.

ECM LOCATIONS

Application Location
All Models Behind Glove Box
NOTE: Components are grouped into 2 categories. The first category is INPUT DEVICESΒ , which are components that control or produce voltage signals monitored by the ECM. The second category is OUTPUT SIGNALSΒ , which are components controlled by the ECM.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.