Alternator Issues

[Tonka]

Hi there, I've been posting in the Electrics forum, but maybe people don't head over there too much?
Basically I'm having some trouble diagnosing what's wrong with my charging system, it's a new alternator, belts are tight, warning lights and buzzer coming on whenever below 2500rpm.

I need to establish beyond doubt that the alternator is fubar. Is there anyone who can help me test the system to make sure that it is the alternator? I specifically need to know what currents and when I should be getting currents to the main plug at the back of the alternator. Also, the 7.5A fuse marked "charge" under the bonnet is only showing up a current when the revs are raised and all the warning lights go out. Why is that and what is that circuit for?

Sorry to re-post, the next step is to find an auto electrician, but I was hoping to avoid more bills.....plus evidently my alternator will have to be sent back to the manufacturers for them to test before it's replaced so I'll be without the truck for weeks and that's not good at the mo.

Here's my thread over there if you wanna peak.

http://www.hiluxsurf.co.uk/showthread.php?t=85211

Many thanks

[jim7564]

have you checked all the earths around the engine,possibly broken or something not earthing properly,multimeter to the alternator and batteries different points around engine bay,
see if anything different with things turned on.my alternator shorted out and had similar problems,
my car also a toyota has a faulty regulator which also causes problems but sometimes works better once lights etc are switched on.

[Tonka]

Just to confirm that the replacement alternator has cured the problems so it was definitely down to the one I fitted 6 months ago being faulty.