Actually for the E34, but most items fit also for E32, one example: How to Test a Bosch Alternator, Contents
1 Wiring Continuity Test
2 Alternator Exciter Circuit Test
2.1 Current Test
2.2 Resistance Checking
2.3 Output Check
3 Diode Assembly Bench Testing
4 Stator Bench Testing
5 Rotor Bench Testing
6 Bearings Bench Testing
7 Brushes Bench Testing

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