The limits of multimeter and oscilloscope checks, and how the MS015, MS013 COM and MS016 testers differ for modern alternators with controlled regulators.
The most accurate alternator check is on a bench after removal, but not every workshop can do this and it takes time. MSG Equipment reviews methods used on the car during servicing.
Measuring 13.8–14.6 V with a multimeter is enough for simple alternators, but digitally controlled regulators may stop charging once the battery is full, which can be mistaken for a fault. An oscilloscope gives more data but cannot reveal regulator faults and needs a skilled operator.
- MS015: only 12 V alternators with controlled regulators, at a low price.
- MS013 COM: conventional alternators and separate regulator testing, single-channel oscilloscope mode.
- MS016: 12/24 V and start-stop alternators, LIN data reading; with a special cable it also works as a starter tester.