Cylinder SUZUKI JIMNY 2005 3.G Service Workshop Manual

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General Description
The ignition system is an electronic (distributorless) ignition system. It consists of the parts as described below
and has an electronic ignition control system.
ECM
It detects the engine and vehicle conditions through the signals from the sensors, determines the most suit-
able 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)
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 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 adjust initial ignition timing automatically.
TP sensor, ECT sensor, MAP sensor and other sensors/switches
Refer to “Electronic Control System” in Section 6E for details.
Although this ignition system does not have a 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 simulta-
neously. 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.
SYSTEM COMPONENTS
1. ECM 7. ECT sensor 13. Monitor connector
2. Ignition coil assembly for No.1 and No.4 spark plugs 8. IAT sensor 14. Knock sensor
3. Ignition coil assembly for No.2 and No.3 spark plugs 9. TP sensor 15. DLC
4. CMP sensor 10. VSS 16. Spark plugs
5. CKP sensor 11. Transmission range switch (A/T)
6. MAP sensor 12. High-tension cords

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On-Vehicle Service
Ignition Spark Test
1) Disconnect all injector connectors (1) from injectors.
2) Remove cylinder head upper cover.
3) Remove spark plug and check it for condition and type refer-
ring to “Spark Plugs” in this section.
4) If OK, connect ignition coil connector to ignition coil assem-
bly and connect spark plug to ignition coil assembly or high-
tension cord. Ground spark plug.
5) Crank engine and check if each spark plug sparks.
6) If no spark is emitted, inspect the related parts as described
under “Diagnosis” earlier in this section.
High-tension Cords
1) Remove cylinder head upper cover and disconnect high-ten-
sion cords (2) from ignition coil assemblies (1) while gripping
each cap.
2) Pull out high-tension cords from spark plugs while gripping
each cap.
3) Measure resistance of high-tension cord (1) by using ohm-
meter.
High-tension cord resistance
4 – 10 k
Ω/m (1.2 – 3.0 kΩ/ft)
4) If resistance exceeds specification, replace high-tension
cord(s). WARNING:
Without disconnection of injector couplers, combustible
gas may come out from spark plug holes during this test
and may get ignited in engine room.
CAUTION:
Removal of high-tension cords together with clamps
will be recommended so as not to damage their inside
wire (resistive conductor).
For the same reason, pull out each connection by grip-
ping cap portion.

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4) If any abnormality is found, adjust air gap, clean with spark
plug cleaner or replace them with specified new plugs.
For iridium/platinum spark plugs, replace them with new
plugs.
Spark plug air gap “a”
1.0 – 1.1 mm (0.040 – 0.043 in.)
Spark plug type
NGK : BKR6E-11, IFR5E11
DENSO : K20PR-U11, SK16PR-A11
5) Install spark plugs and torque them to specification.
Tightening torque
Spark plug : 25 N·m (2.5 kg-m, 18.0 lb-ft)
6) Install ignition coil assemblies referring to “Ignition Coil
Assembly” in this section.
7) Install high-tension cords securely by gripping their caps.
Ignition Coil Assembly (Including Ignitor)
1) Disconnect negative cable at battery.
2) Remove cylinder head upper cover.
3) Disconnect ignition coil connector.
4) Disconnect high-tension cord (3) from ignition coil assembly
(2).
5) Remove ignition coil bolts (1) and then pull out ignition coil
assembly. NOTE:
NGK IFR5E11 or DENSO SK16PR-A11 is highly recom-
mended for better engine starting performance under –
25°C (– 13°F).
CAUTION:
When servicing the iridium/platinum spark plugs (slender
center electrode type plugs), do not touch the center
electrode to avoid damage to it. The electrode is not
strong enough against mechanical force as it is slender
and its material is not mechanically tough.

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6) Measure resistance between terminals as follows by using
analog type ohmmeter.
If check result is not satisfactory, replace ignition coil assem-
bly.
Secondary coil resistance
“a” – “b” : 7.5 – 14 k
Ω (at 20°C, 68°F)
7) Install ignition coil assembly.
8) Tighten ignition coil bolts, and then connect ignition coil cou-
pler.
9) Install high-tension cord to ignition coil assembly while grip-
ping its cap.
10) Install cylinder head upper cover.
Crankshaft Position Sensor (CKP Sensor)
Refer to “Crankshaft Position Sensor” in Section 6E for removal,
inspection and installation.
Ignition Timing
INSPECTION
1) When using SUZUKI scan tool (1), connect SUZUKI scan
tool to DLC (2) with ignition switch OFF.
Special tool
(A) : SUZUKI scan tool
2) Start engine and warm it up to normal operating tempera-
ture.
3) Make sure that all of electrical loads except ignition are
switched off.
4) Check to be sure that idle speed is within specification.
(Refer to “Idle Speed/Idle Air Control Duty Inspection” in
Section 6E.)
NOTE:
Ignition timing is not adjustable. If ignition timing is
out of specification, check system related parts.
Before starting engine, place transmission gear shift
lever in “Neutral” (shift selector lever to “P” range for
A/T model), and set parking brake.