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.
Control System
* SFI system
The SFI system monitors the engine condition through the signals received from each sensor by the engine control module. And a control signal is output from TERMINALS #1, #2, #3 and #4 of the engine control module to operate the fuel injector (Inject the fuel). The SFI system uses the engine control module to control the fuel injection operation in response to the driving conditions.
* ESA system
The ESA system monitors the engine conditions through the signals received by the engine control module from each sensor. The best ignition timing is decided according to this data. Then the data stored in the engine control module and the control signals are output from TERMINALS IGT1, IGT2, IGT3, IGT4. These signals control the ignition coils (Igniter) to provide the best ignition timing for the driving conditions.
* Heated oxygen sensor heater control system
The heated oxygen sensor heater control system turns the heater on when the intake air volume is low (Temp. of exhaust emissions is low), and warms up the heated oxygen sensor to improve detection performance of the sensor. The engine control module evaluates the signals from each sensor, and outputs current to TERMINAL HT1B to control the heater.
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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.