300ZX V6-2960cc DOHC (VG30DE) (1990)
Engine Control Module: All Technical Service Bulletins
Engine Controls - ECM Testing and Notes
Classification:
EL93-028
Section:
Electrical System
Reference:
TECHNICAL BULLETIN NTB93-161
Models:
All Models
Date:
November 5, 1993
ELECTRONIC CONTROL UNITS
Electronic control units (ECU's) control the operation of numerous electrical systems and components on Nissan vehicles. The ECU's do this by either
controlling the supply voltage or ground path of an electrical component. The following is an explanation of how these systems work and what
precautions should be taken while performing diagnostic procedures.
Systems controlled by electronic control units have three (3) basic requirements, Inputs, Controller Logic and Outputs.
Inputs
Sensors and switches provide electrical signals to the control unit. These signals are provided to the ECU to inform it of various vehicle operating
conditions. The electrical inputs can be either analog or digital signals. However, all of the signals are converted to digital signals before the ECU can
process the information.
Control Logic
The ECU uses the electrical input signals to determine what the system should do. This decision may be based on a few or many inputs. After processing
the information the ECU will provide a signal (output) to various electrical components.
Outputs
The signal that the ECU puts out to an electrical component (actuator) is called the output. These output signals are what operate and control the system.
Digital Input Signals