Alternator/Charging system electrical help needed please.

[silver88turbo]

Ok here is the problem. The battery is not being charged, the brake warning light and battery light are on. I took the alternator to O'Reileys to get tested and it checked out fine (14v) but I dont think they put a load on it. The alternator ground is good, S and IG both have continuity to the + terminal when they should. But I dont understand how the circuit to L works (what should I be checking for?). It seems the brake warning light gets power from the IGN fuse, and then L is acting as a ground then...? But why? And why is the diode needed? Can someone explain this cicuit to me in detail and offer any suggestions as to what my problem is?

Thanks....electrical shit is not my strong point.

 

[aye mate]

http://www.supramania.com/forums/showthread.php?t=15567 Some good info in here.

 

[Halsupramk3]

when the brake out light and the battery light and i think the radiator light all light up that means your diode is out in the alternator. Current will flow backwards and light up the lights from their ground point. The alternator will also drain your battery while the car is off. I think the diode test is a separate test from a load test at the auto parts store.