Alternator Output Bat Wire Resistance Test
NOTE:
ALTERNATOR OUTPUT BAT WIRE RESISTANCE TEST will show amount of voltage drop across alternator output wire between alternator BAT terminal and positive battery post.
- Before performing this test, ensure battery is fully charged. Turn ignition off. Disconnect negative battery cable. Disconnect alternator output wire from alternator BAT terminal. See Fig 2.
- Using a 0-150 ampere scale DC ammeter, connect positive ammeter lead to alternator BAT terminal and negative ammeter lead to disconnected alternator output BAT wire. See Fig 1.
- Using a voltmeter (0-18 volts minimum), connect positive voltmeter lead to disconnected alternator output BAT wire and negative lead to positive battery cable.CAUTION: Alternator has one field terminal (Dark Green wire) and one ignition terminal (Dark Blue wire). DO NOT connect a grounded jumper wire to ignition terminal (Dark Blue wire), or severe wiring damage will result. See Fig 2.
- Remove air duct hose between PCM and air cleaner. Connect one end of jumper wire to ground, and other end to alternator field terminal (Dark Green wire) at rear of alternator. Alternator is now full-fielded.
- Connect tachometer to engine. Reconnect negative battery cable. Ensure carbon pile rheostat or load tester is in OFF position, then connect leads to battery terminals.
- Start engine and immediately reduce engine speed to idle. Adjust engine speed and carbon pile to maintain 20 amps flowing in circuit. Observe voltmeter reading. Voltage drop should not be more than .5 volt.
- If voltage drop is more than .5 volt, inspect, clean and tighten all connections between alternator BAT terminal and positive battery post. Voltage drop test may be performed at each connection to locate connection with excessive resistance. If resistance tests are satisfactory, reduce engine speed, turn off carbon pile. Turn off ignition switch.
- Disconnect negative battery cable. Remove test ammeter, voltmeter, carbon pile and tachometer. Remove jumper wire between alternator field terminal (Dark Green wire) and ground. Connect alternator output wire to alternator BAT terminal. Reconnect negative battery cable. Install air duct hose between PCM and air cleaner.