Ignition System; General Description; Ignition System Construction - Suzuki Grand Vitara Service Manual

1H-1 Ignition System:

Ignition System

Ignition System Construction

The ignition system is an electronic (distributor less)
ignition system. Especially a direct ignition system is
adopted for J20 engine. They consists of the parts as
described below.
• ECM
It detects the engine and vehicle conditions through
the signals from the sensors, determines the most
suitable ignition timing and time for electricity to flow
to the primary coil and sends a signal to the ignitor
(power unit) in the ignition coil assembly.
• Ignition coil assembly (including an ignitor and an
ignition coil)
The ignition coil assembly has a built-in ignitor which
turns ON and OFF the current flow to the primary coil
according to the signal from ECM. When the current
flow to the primary coil is turned OFF, a high voltage is
induced in the secondary coil.
• High-tension cords (for M16 engine) and spark
plugs
• CMP sensor (Camshaft position sensor) and CKP
sensor (Crankshaft position sensor)
Using signals from these sensors, ECM identifies the
specific cylinder whose piston is in the compression
stroke, detects the crank angle and adjusts initial
ignition timing automatically.
• TP sensor, ECT sensor, MAP sensor, MAF sensor,
IAT sensor, knock sensor, wheel speed sensor
(VSS) and other sensors / switches
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General Description

For M16 engine, this ignition system does not have a
S5JB0A1801001
distributor, it has two ignition coil assemblies (one is for
No.1 and No.4 spark plugs and the other is for No.2 and
No.3 spark plugs). When an ignition signal is sent from
ECM to the ignitor in the ignition coil assembly for No.1
and No.4 spark plugs, a high voltage is induced in the
secondary coil and that passes through the high-tension
cords and causes No.1 and No.4 spark plugs to spark
simultaneously. Likewise, when an ignition signal is sent
to the ignitor in the other ignition coil assembly, No.2 and
No.3 spark plugs spark simultaneously.
For J20 engine, although ignition system does not have
a distributor and high-tension cords but each cylinder
has an ignition coil assembly (ignitor and ignition coil)
and the secondary voltage which occurred in the ignition
coil is sent to the spark plug directly. Also, the signal (s)
are sent from the CMP sensor to ECM so as to control
each ignition coil independently through the ignitor (in
ignition coil assembly).
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