checking oil MITSUBISHI 380 2005 Workshop Manual

HOW TO DIAGNOSE
GENERAL 00E-6
5. Ohmmeter
An ohmmeter is used to check continuity or measure
resistance of a switch or coil. If the measuring range has
been changed, the zero point must be adjusted before
measurement.
CHECKING FUSESM1001005000044
A blade type fuse has test taps provided to allow checking of
the fuse itself without removing it from the fuse block. The fuse
is okay if the test light comes on when its one lead is connected
to the test taps (one at a time) and the other lead is grounded.
Remember to turn the ignition switch to ON to ensure all cir-
cuits are live.
CAUTIONS IN EVENT OF BLOWN FUSE
When a fuse is blown, there are two probable causes. One is
that it is blown due to flow of current exceeding its rating. The
other is that it is blown due to repeated on/off current flowing
through it. Which of the two causes is responsible can be easily
determined by visual check as described below.
1. Fuse blown due to current exceeding rating
The illustration shows the state of a fuse blown due to this
cause. In this case, do not replace the fuse with a new one
hastily since a current heavy enough to blow the fuse has
flowed through it. First, check the circuit for shorts and check
for abnormal electric parts. After correcting shorts or
replacing parts, use only a fuse of the same capacity as a
replacement. Never use a fuse of larger capacity than the
original fuse. If a larger capacity fuse is used, electric parts
or wiring could be damaged, or could start a fire.
2. Fuse blown due to repeated turning current on and off
The illustration shows the state of a fuse blown due to
repeated current on/off. Normally, this type of problem
occurs after a fairly long period of use and is less frequent
than above. In this case, simply replace with a new fuse of
the same capacity.

HOW TO DIAGNOSE
GENERAL 00E-8
CHECKING RELAYSM1001004900152
1. By using a relay, a heavy current can be turned on and off by
a switch using much less current. For example, in the circuit
shown here, when the switch is turned on (closed), current
flows to the coil of the relay. Then, its contact is turned on
(closed) and the light comes on. The current flowing through
the switch is much less than that for the light.
2. When current flows through the coil of a relay, its core is
magnetized to attract the iron piece, closing (ON) the
contact at the tip of the iron piece. When the coil current is
turned off, the iron piece returns to its original position by a
spring, opening the contact (OFF).
3. Relays may be classified as the normally open-type or the
normally closed-type, depending on their contact
construction.
NOTE: The deenergised state means that no current is flow-
ing through the coil. The energised state means that current
is flowing through the coil.
(1) The normally open-type
When a normally open relay as illustrated here is
checked, there should be no continuity between terminals
3 and 4 when the relay is deenergised. There should be
continuity between terminals 3 and 4 when battery
voltage and ground are applied to terminals 1 and 2. The
relay condition is determined by this check.
NOTE: Check the relay in both situation which is
energised and is not energised.
(2) The normally closed-type
When a normally closed relay as illustrated here is
checked, there should be continuity between terminals 3
and 4 when the relay is deenergised. There should be no
continuity between terminals 3 and 4 when battery
voltage and ground are applied to terminals 1 and 2. The
relay condition is determined by this check.
NOTE: Check the relay in both situation which is
energised and is not energised.