On-Vehicle Service; Engine Electrical; Alternator Output Line Voltage Drop Test - Mitsubishi Lancer Evolution-VII Workshop Manual

16-4

ON-VEHICLE SERVICE

ALTERNATOR OUTPUT LINE VOLTAGE DROP TEST

Alternator
This test determines whether the wiring from the
alternator "B" terminal to the battery (+) terminal
(including the fusible line) is in a good condition
or not.
(1) Always be sure to check the following before
the test.
Alternator installation
D
Alternator drive belt tension
D
(Refer to GROUP 11 - On-vehicle Service.)
Fusible link
D
Abnormal noise from the alternator while
D
the engine is running
(2) Turn the ignition switch to the "LOCK" (OFF)
position.
(3) Disconnect the negative battery cable.
(4) Disconnect the alternator output wire from the
alternator "B" terminal and connect a DC test
ammeter with a range of 0 - 100 A in series

ENGINE ELECTRICAL -

Voltmeter
+
Terminal B
Charging System
+ -
Ammeter
-
between the "B" terminal and the disconnected
output wire. (Connect the (+) lead of the
ammeter to the "B" terminal, and then connect
the ( - ) lead of the ammeter to the disconnected
output wire.)
NOTE
An inductive-type ammeter which enables
measurements
disconnecting the alternator output wire should
be recommended. Using this equipment will
lessen the possibility of a voltage drop caused
by a loose "B" terminal connection.
(5) Connect a digital-type voltmeter between the
alternator "B" terminal and the battery (+)
terminal. (Connect the (+) lead of the voltmeter
to the "B" terminal and the connect the ( - ) lead
of the voltmeter to the battery (+) cable.)
Battery
to be taken without