Part 2 Diagnosis Of Automotive Troubles; Fuse Testing: Check The Fuse To See If It Is Blown Out; Switch Testing: Check The Switch To See If It Can Work Correctly - UNI-T UT105 Operating Manual

Measurement Operation(11)

Part 2 Diagnosis of Automotive Troubles

The digital multimeter is a tool for the very effective
diagnosis of the troubles with the electronic systems of
the automobile. This part gives a special introduction as
to how the multimeter is used to diagnose any trouble
with a fuse, switch, solenoid, relay, starting and charging
systems, ignition system, fuel system and engine sensor.
A.Fuse Testing: Check the fuse to see if it is blown out.
1. Set the rotary switch to 200 .
2. As prompted at the LCD connect terminal, insert the
red test lead into the terminal and the black one into
the COM terminal.
3. Short circuit the red and black test lead probes, when
the reading of the meter should be displayed between
0.2 and 0.5 If it is more than 0.5 , check the test
leads to see whether they are well connected.
4. Connect the red and black test lead probes in parallel
to the two ends of the fuse, when the reading of the
meter should be displayed less than 10 , indicating
that the fuse is good. When the display is overload
"1", it is shown that the fuse has been blown out.
It must be replaced with a fuse of the same type
l
and size.
B.Switch Testing: Check the switch to see if it can
work correctly.
1. The same as in Items 1 to 3 (Fuse Testing).
2. Connect the black test lead probe to one end of the
switch and the red one to another end. When the
switch is connected, the reading of the meter should
be displayed less than 10 . When the switch is cut
off, overload "1" should be displayed as the reading
of the meter.
Model UT105: OPERATING MANUAL
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