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System Description
 
 
SYSTEM DIAGRAM
Component partsFunction
Crankshaft position sensorCrankshaft Position Sensor.
Exhaust camshaft position sensorExhaust Camshaft Position Sensor
Mass air flow sensor
(With intake air temperature sensor)
Mass Air Flow Sensor (With Intake Air Temperature Sensor)
Engine coolant temperature sensorEngine Coolant Temperature Sensor
Throttle position sensorElectric Throttle Control Actuator
Accelerator pedal position sensorAccelerator Pedal Position Sensor
BatteryECM receives the battery voltage signal.
Knock sensorKnock Sensor
Combination meterECM receives the vehicle speed signal via CAN communication.
TCMECM receives the park/neutral position signal via CAN communication.
ECMECM
Ignition coil
(With power transistor)
Ignition Coil With Power Transistor
 
 
SYSTEM DESCRIPTION
Firing order: 1 - 3 - 4 - 2
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor signal. Computing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revised by the ECM according to the other data stored in the ECM.
  • At starting
  • During warm-up
  • At idle
  • At low battery voltage
  • During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition. The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.