Output Wire Voltage Drop Test

1. Ensure battery is fully charged.
2. Start engine and allow it to reach operating temperature.
3. Clean all dirt and corrosion from a small spot on alternator housing.
4. Turn on the following:
a. Headlamps on high beam.
b. A/C system.
c. A/C heater blower switch to high.
d. Radio.
e. Rear window defogger.
5. Connect the positive lead of a voltmeter with a millivolt scale to alternator housing attach negative lead of voltmeter to battery negative post.
6. Voltage drop should not exceed 0.2 volts. If voltage drop exceeds 0.2 volts, remove alternator and thoroughly clean surfaces between alternator and mounting bracket.