Testing Altenator

[Tesla]

Testing Alternator

My friends battery keeps going flat, he replaced the battery but now that is flat to.

So either he has a short or a dodgy alternator. It's a '96 Fiesta (Mk3?, the boxy type) and has a 1.0l engine.

What is the correct procedure for testing how well the alty is functioning?

 

[Tesla]

Get the car bump started, the voltage reading with the engine running should be a fair bit higher than 12v (probably 14-16v), then turn the engine off and take a reading (should be around 12-13v).

If the readings are the same, or very close, then it'd be a pretty certain bet that the altenator is shot.

Where should I measure it across? The battery terminals?