Charging Circuit Resistance Test

Fig. 5 Charging circuit resistance test. 1984---87 exc. units w/regulator in engine electronics:

EXC. UNITS W/REGULATORS IN-ENGINE ELECTRONICS
When testing alternators except 100 and 114 amp units, use a 0---100 amp ammeter. When testing 100 and 114 amp alternators, use a 0---150 amp ammeter.
1. Disconnect battery ground cable. Disconnect "Batt" lead at the alternator.
2. Complete test connections as shown.
3. Connect battery ground cable, start engine and operate at idle.
4. Adjust engine speed and carbon pile to obtain 20 amps in the circuit and check voltmeter reading. Reading should not exceed .7 volts. (.5 volts on 1984---88 models). If a voltage drop is indicated, inspect, clean and tighten all connections in the circuit. A voltage drop test at each connection can be performed to isolate the trouble.

Fig. 6 Charging circuit resistance test. 1985---88 units w/regulator in engine electronics:

UNITS W/REGULATOR IN-ENGINE ELECTRONICS
1. Disconnect battery ground cable and the "Bat" lead from alternator output terminal.
2. Complete test connections as shown.
3. Remove air hose between power module and air cleaner, then the wiring harness electrical connector.
4. Connect a suitable jumper wire from wiring harness connector green wire terminal to ground. Do not connect blue J2 lead of wiring electrical connector to ground.
5. Connect battery ground cable, then start engine and operate at idle.
6. Adjust engine speed and carbon pile rheostat to obtain 20 amps in the circuit and check voltmeter reading. Reading should not exceed .5 volts. If a higher voltage drop is indicated, inspect, clean and tighten all connections in the circuit. A voltage drop test at each connection can be performed to isolate the problem.