Service Manual

Alternator Regulated Voltage Test
1. Install an ammeter between the positive (+) terminal
of the battery and terminal “B” of the alternator.
2. Ground alternator terminal “
L” through a voltmeter.
3. Note that the voltmeter shows 0 volts when the
ig
nition key switch is in the OFF position. The voltmeter
will show voltage lower than battery voltage when the
ignition key switch is in the ON position (engine not
running).
4. Start the engine.
5. Run the engine with the alternator at 1300 and 2500
rp
m and observe the voltmeter with all accessories OFF,
Ammeter below 5 A. Regulated voltage will decrease
slightly as alternator temperature increases.
Regulated voltage: 13.5 V
Alternator Output Test
Figure 34
1. Disconnect the battery ground (–) cable.
2. Install an ammeter between the positive (+) terminal
of
the battery and terminal “B” of the alternator.
3. Ground alternator terminal “B” through a voltmeter.
4. Connect the battery ground (–) cabl
e.
5. Start the engine.
6. Run the engine with the alternator at 2500 and 5000
rp
m and observe the voltmeter with all electrical load
applied. Read the maximum indication on the ammeter
with the voltmeter showing 13.5 V.
Figure 35
Output Characteristics (Hot):
21 A at 2500 rpm
37 A at 5000 rpm
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