IG-1
Ignition system
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IG-2 Ignition system-preventive measures, Circuit diagram /vehicle inspection of ignition system
Preventive measures
Great Wall automotives are driven by petrol engine, which works after the mixture of petrol and air has been
ignited by the high-voltage electric spark produced by one set of ignition system installed inside the engine. And
the ignition system has such function as to transform the low-voltage provided by battery into a high-voltage
current able to ignite the inflammable gas mixture inside engine cylinder; and to distribute the high-voltage
current on time to the spark plug at each engine cylinder as per engine working procedure. And electric sparks
produced between electrodes of spark plug will ignite the inflammable gas mixture to push the piston for actions,
and to drive the connection rod of crankshaft, and to make the engine working.
The preventive measures are given below
1.If the engine can not be started, do not have the ignition key being connected for over ten minutes;
2.During the connection between system and the tachometer, the test line of tachometer shall be connected to
the negative terminal of ignition coil;
3.To prevent any damage on igniter or ignition coil, do not have the terminal of tachometer contacted withground
4.Do not dismantle the battery while engine is running;
5.Always verify whether the igniter has been connected well with the cover.
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Ignition system-Circuit diagram /vehicle inspection of ignition system
Circuit diagram of ignition system as shown in the figure below
ignition fuse
electronic ignition timing A
high-tension coil
electronic ignition timing B
ignition coil
spark plug
fuse
1-3-4-2 ignition sequence
battery
Ignition system- Circuit diagram /vehicle inspection of ignition system IG-3
Vehicle inspection
Spark plug test check the form of spark plug
1. Remove the high-tension wiring from spark plug
2. Remove the spark plug
3. Spark plug needs to be installed on each high-tension wiring
4. Spark plug will be grounded
5. Check whether the ignition works when engine starts running.
Note Following test may be performed when the
ignition does not work.
Spark test
you can
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Check the resistance of high-voltage Change the high voltage resistance line
damping wiring You can’t
you can
Check the power supply to ignition coil
1. Place the ignition switch to position “ON” Check the line between spark
plug and ignition coil
2. check whether an battery voltage exists on You can’t
the positive connection line of ignition coil
you can
Check the resistance of ignition coil
Delphi
Model ITMS-6 primary grade
secondary grade Change the ignition coil
you can’t
Model MT20U primary grade
secondary grade
United Electronic model 2 2
primary grade
secondary grade
you can
Perform other ignition inspections
IG-4 Ignition system- Inspection on high-tension wiring, inspection on spark plug
Inspection on high-tension wiring
1. Remove the high-tension wiring. Hold the rubber cover with
hand, removing the high tension wiring from the spark plug
carefully.
Note Dragging, pulling or bending the hightension wiring might
cause some damages on internal conductors.
2. Check the resistance of high-tension wiring
Resistance may be measured with an ohmmeter when
the cover is not opened. Unit K
United
Position Delphi
electronic
Cylinder 1 3.80—5.50 2.96—4.72
Cylinder 2 4.00—5.70 2.96—4.72
Cylinder 3 4.50—6.50 2.96—4.72
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Cylinder 4 5.30—7.70 5.08—8.30
Specification of high-voltage resistance line:(16 3.2)K /m
Inspection on spark plug
1. Remove the spark plug.
2. Clean the spark plug.
Clean the spark plug with cleaner or steel wire brush.
3. Check the spark plug visually
Check whether the electrode of spark plug has been abraded, whether
screw thread or insulator has been damaged. Spark plug needs to be
changed whenever there’s any abnormality.
Recommended spark plug F6RTC
4. Adjust the clearance of electrodes.
Following a careful bending of bypass electrode, correct electrode
clearance may be acquired by adjustment.
Correct electrode clearance (1.0 1.2)mm
5. Install the spark plug
Tightening torque 18N m
