Battery warning light always on

[Dan_GTi8v]

Tried 2 alternators and battery light is still constantly on with engine running. Any ideas what it could be? It's an AUM in a mk3 so I dont have the fusebox on top of the battery and fairly sure there is no fuse or relay for it

cheers

[stevelfc]

is the belt and battery itself any good

[Dan_GTi8v]

belt is good, battery was good when it first started but I've now been running with it for a week so have manually charged it 4 or 5 times. Was hoping the new alt today would fix it but no luck
I'll be getting the alt tested on saturday with a multimeter on the battery but dunno what else to check 

[richw911]

How much voltage is at the battery with the engine running?

[Dan_GTi8v]

wont know this till saturday But as its my 2nd alternator was just wondering what else I could check

[richw911]

wont know this till saturday But as its my 2nd alternator was just wondering what else I could check

Wiring to the alternator? The plug?

[Dan_GTi8v]

Plug looks fine, I guessed it would be ok as the light comes on. wiring is fine as far as I can see, but can only see it as far as the battery then it goes into the main loom. Everything is pointing towards the alt being shagged I guess Just sux I only got this one yesterday I'll update on saturday with the rusults of multimeter on battery

[Wayne]

Check and see if it is charging as a 1st step.

[Dan_GTi8v]

It's deffinatly not charging, I've been putting it on a manual charger after 3 or 4 trips and its always on around half power. I'm keeping an eye not to overcharge the battery but not sure how much longer its gonna last 

Should be putting a multimeter on it tonight, also been suggested to run 12v to the positive pin on the plug and if it charges just swap over for my old mk3 alt which only has 1 wire going to it instead of the 2 on the mk4 alt

[Ant1981]

Rectifier.