LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 1992 >> Q45 Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> Theory and Operation >> Engine Controls - Theory & Operation >> Computerized Engine Controls >> Electronic Control Unit (Ecu)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Electronic Control Unit (Ecu)

ECU consists of a microcomputer, inspection light, diagnostic mode selector, connectors and wiring for voltage signal input, voltage signal output and power supply. See ECU LOCATION table. Unit is not serviceable and should not be opened. Inspection light is provided on side of unit so system operation can be checked. Control unit contains memory and logic circuits, which enable it to interpret sensor inputs and control various engine systems.

Continuous fused battery power is provided to ECU terminal No. 46 (G20) or terminal No. 58 (M30 and Q45). Battery power to drive ECU internal components is provided through ECCS relay, which is energized by ECU when ignition switch is turned to ON position.

ECU LOCATION

Application Location
G20 Under Dash, In Center Console
M30 & Q45 Under Dash, Behind Right Kick Panel
NOTE: The ECCS components are grouped into 2 categories. The first is INPUT DEVICES, which are components that control or produce voltage signals monitored by ECU. The second category is OUTPUT SIGNALS, which are components controlled by ECU.