User Manual

UT108/109 OPERATING MANUAL
48
Part 2 Diagnosis of Automotive Troubles
The Meter 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 Meter 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 Ω.
2. Insert the red test lead into the Ω 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 Ω and 0.5 Ω. If it is more than 0.5 Ω, 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 Ω, indicating that the fuse is
good. When the display is overload “OL”, it is shown that the fuse has been blown out.
Warning:
It must be replaced with a fuse of the same type and size.