Output Test

Connecting Test Equipment For Output Test:

1. Check system for loose or broken ground straps, loose or damaged V-belt, charging light operating properly and proper tightening of alternator.
2. Disconnect battery ground and positive cables.
3. Connect battery cutout switch SUN VAT-40 or SUN VAT-60 or their equivalents to battery positive post, then the positive cable to battery cutout switch. Ensure battery cutout switch is in On position.
4. Connect ammeter, voltmeter and load resistance as shown in Fig. 1. Ensure load resistance is connected to battery positive cable.
5. Connect battery ground cable, switch off all electrical accessories, then start engine and run at 3000 RPM.
6. Set load resistance so that ammeter shows approximately 20 amps, then turn battery cutout switch to Off position.
7. On V8 Quattro models, adjust load resistance until ammeter reads 71 amps, then check that voltmeter reads between 12.5 and 14.5 volts.
8. If voltmeter reads between 12.5 and 14.5 volts, system is operating properly.
10. If voltmeter does not read between 12.5 and 14.5 volts, substitute a known good voltage regulator and repeat test.
11. If voltmeter reads between 12.5 and 14.5 volts, discard original regulator and replace with new part.
12. If voltmeter does not read between 12.5 and 14.5 volts, replace alternator.