Volvo T5 Charging issues

[Justin S]

Can anyone help with this. A colleagues at works T5 just suddenly stopped the other day and it looked like an alternator problem. He had already put a new battery on about a month ago. The alternator was taken off and checked at a repair shop and deemed perfect in operation. The car when started, the battery light goes out on the dash and all seems OK, but then the lights go dim and battery goes flat, so is not actually charging. The battery is checked as OK. Is there any fuses or inline devices that might have a connection issue ? cheers for any help.I have also stuck this in the Volvo section.

[dibo5171]

While the engine is running check the alternator on AVO meter or multitester. The charging should not be less than 13V

[fatjon]

Check the voltage at the alternator and at the battery when the engine is running. There is a thermal fuse between them on some cars. Voltage across battery terminals should be higher with engine running, minimum 13V higher the better within reason. Over 14.8v is too much I think.

[Justin S]

I believe they have had a meter on the battery before they removed the alternator thinking it was faulty.