2.10.3 System Working Principle
2.10.3.1 System Working Principle
When the ignition switch is at "ON" or "ST" position, the ignition
switch wiring harness connector IP23 terminal No.1 and
terminal No.2 are connected, so that IG1 relay coil forms a
complete circuit.Battery voltage passes through the fuses
EF01, EF22, IG1 Relay, fuse IF30 to reach the ignition coil,
supplies power to the ignition coil.
Crankshaft position sensor is a magnetic inductive speed
sensor. Crankshaft position sensor signal plate and the
flywheel is an integrated part. When the engine rotates, so does
the crankshaft position sensor signal drive plate. So the sensor
produces an alternating signal. This signal is transmitted to
ECM. ECM calculates the current crank angle based on this
signal in order to determine the piston reaches the TDC,
directly affecting the accuracy of the ignition advance angle
control. This sensor signal is a crucial input signal in the ignition
system. When ECM can not receive the signal, the ignition
system can not work. ECM harness connector EN01 terminals
No.46 and No.47 receive crankshaft position sensor input.
After calculation, ECM obtains the ignition advance angle.
ECM harness connector EN01 terminal No.3 controls cylinders
No.1 and No.4 ignition, terminal No.7 cylinders No.2 and No.3
ignition.
For crankshaft position sensor technical specifications. Refer
to
2.2.1.2
Temperature Sensor Temperature and Resistance
Correlation
.
For knock Sensor technical specifications. Refer to
2.2.1.2
Temperature Sensor Temperature and Resistance
Correlation
.
Note
When the vehicle Anti-theft alarm system and engine
anti-theft locking system are activated, ECM does not
allow ignition coil to be ignited. The ignition system is
inoperative at this time.
Engine
Ignition System JL4G18-D
2-519