User Manual

Table Of Contents

UT108/109 OPERATING MANUAL

I. Ignition System Testing

1.Ignition Coil Testing

(1) Before the operation, cool the engine and cut off the ignition coil.

(2) Set the rotary switch to the Ω. Insert the red test lead into the Ω terminal and the black

one into the COM terminal. Test the primary coil of the ignition coil.

(3) Short circuit the red and black test lead probes. Their short circuit resistance should

be less than 0.5 Ω. 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.

(4) 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 gure 16.) See the detailed positions

in various kinds of automotive manuals.

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 Ω and 2.0 Ω.

(5) Set the rotary switch to the 200 kΩ and test the primary coil of the ignition coil.

(6) Connect the red test lead probe to the secondary outlet and the black one to the

primary “-” pole. Refer to various kinds of automotive manuals for the details.