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.
Engine Control Module (ECM)
The ECM is located on a bracket in a central position on the engine compartment firewall. The ECM is attached to a housing and secured with 4 screws. The housing is located in the bracket and locked in position.
The ECM is supplied with battery voltage from fuses located in the BJB. A permanent battery supply is provided to ensure adaptive data is not lost when the engine is switched off.
A regulator, located within the ECM, supplies a 5V current to internal components such as the micro-processor unit. Other components or functions requiring full battery voltage are controlled by external relays or internal power stages.
The micro-processor within the ECM receives signals from different components and control modules and uses a program within the ECM software to interpret the signal information and issue signals which relate to how the engine components and functions should be controlled.
The ECM receives inputs from the following:
- CMP sensors
- CKP sensor
- Fuel rail pressure sensor
- MAF sensor
- Knock sensors
- Fuel rail temperature/pressure sensor
- ECT sensor
- Engine oil level/temperature sensor
- Manifold Absolute Pressure (MAP) sensor
- Electric throttle - Throttle Position (TP) sensor
- APP sensor
- Fuel tank leakage monitoring module (NAS only)
- Cooling fan control
- Heated Oxygen sensors (HO2S)
- Stop lamp switch (via Central Junction Box (CJB))
- Speed control inhibit switch
- Intake Air Temperature (IAT) sensor
- Ambient Air Temperature (AAT) sensor
- Transmission Control Module (TCM).
The ECM sends outputs to the following:
- Main relay
- Air Conditioning (A/C) relay
- Fuel injectors
- Ignition coils
- Engine cooling fan control
- Electric throttle
- Electric fuel pump driver module
- Variable Camshaft Timing (VCT) solenoids
- Starter relay control
- Variable intake manifold control valves
- Variable inlet cam profile switching solenoid valves
- Transmission Control Module (TCM).
Use the Manual With the Right Hardware
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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.
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