Auxiliary Drive Belt, Tensioner & Idler

[cheshired5]

Have you used a mirror to look all around the alternator for markings?

I would also get another multimeter for a second opinion or diagnostics to find out system voltage because unless things are radically on newer cars, that's a bad figure if it's correct.
If it's 17.5, what's the variation on that when you load up the electrical system?

[Craig S]

I have a new Multimeter and the tests all came back as you would expect.

Battery at just over the 12 volt mark, with the car running it is around 14.2 to 14.5 volts.

The issue has stopped now. I am putting it down to belt slip as the issue only ever happened twice and both times it happened just after the car was on full lock going into or out of a parking space.

Will leave it and see how things fare in the future.

Thanks for the help Cheshired5