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Model UT107: OPERATING MANUAL
I. Ignition System Testing
1. Ignition Coil Testin
Before the operation, cool the engine and cut off the
ignition coil.
Set the rotary switch to the 200 . As prompted at
the LCD connect terminal, insert the red test lead
into the terminal and the black one into the
COM
terminal. Test the primary coil of the ignition coil.
Short circuit the red and black test lead probes. Their
short circuit resistance should be less than 0.5 . If
it is more, check the test lead to see if it is loose or
damaged. If it is damaged, replace it with a new one.
Connect the red test lead probe to the primary “+”
pole of the ignition coil and the black one to the
primary “-” pole of the coil. (see figure 15.) See the
detailed positions in various kinds of automotive
manuals.
(1)
(2)
(3)
(4)
(figure 15)
Warning
The reading of the testing becomes the actual
tested resistance only after the reduction of the
short-circuit values of the test leads.
The primary resistance is generally between 0.3
and 2.0 .
l
l
Secondary Coil
Primary
Coil
Red
Black
Cylindrical
Ignition Coil
