Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSNISSAN-DATSUN2004SENTRA L4-2.5L (QR25DE)REPAIR AND DIAGNOSISPOWERTRAIN MANAGEMENTRELAYS AND MODULES - POWERTRAIN MANAGEMENTRELAYS AND MODULES - COMPUTERS AND CONTROL SYSTEMSENGINE CONTROL MODULEDESCRIPTION AND OPERATION
2004 Nissan-Datsun Sentra L4-2.5L (QR25DE)
Engine Control Module: Description and Operation
2004 Nissan-Datsun Sentra L4-2.5L (QR25DE)SECTION Description and Operation
ECM
Component Description
The ECM consists of a microcomputer and connectors for signal input and output and for power supply. The ECM controls the engine.
ECM POWER SUPPLY
Component Description
Battery voltage is supplied to the ECM even when the ignition switch is turned OFF for the ECM memory function of the DTC memory, the air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc.
Component Description
The ECM consists of a microcomputer and connectors for signal input and output and for power supply. The ECM controls the engine.
ECM POWER SUPPLY
Component Description
Battery voltage is supplied to the ECM even when the ignition switch is turned OFF for the ECM memory function of the DTC memory, the air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.