Battery light on with no key, off with key!?

Hi



This morning my wife’s Disco (92 200Tdi) battery was flat as it could be. I dumped by Defender battery in to get her to work, all seemed ok.

When she got to work and turned the ignition off, the battery warning light came on (with the key removed!), she left it like that all day, started the engine first time and drove home.

Now I have a Disco with the warning light on all the time the ignition is off, and when I turn the key to the point where the dash lights go on the battery light goes out! the light stays out when the engine is running and the battery seems to charge (or at least its not flat yet and seems to have plenty of power).

REALLY lost on this one, is it a new alternator? Any clues?

Expecting an early start swapping batteries tomorrow. L


YeryYellow (now more black and oily again!)

YES its deff the alternator m8

I would recomend you remove the battery termanal over night as the faulty alternator may kill your battery again

Thanks Bellautos

I'm off to remove it before it gets dark,
Out of interest, any idea how the circuit is working to get this combination of lights?

OilyVeryYellow.

im not to clever on the internals , I no there is a voltage regulator in there and a rectifyer amongst other things but what exactley goes im not to sure .

just out of curiosity have a look at the back of the alternator and see if there is a small removable bush pack that you can remove with 3 5.5mm headed blots .

because if so you can just change this part of the alternator on this type as long as the armature is ok, which it should be if its still charging.

some are different in how they are made and that part carnt be removed .

Just got it off and can't see anything. Seems to be dated '92' so possibly the original with 200k+ on the clock, (200Tdi’s are great!) The wife's got a lift so I'm just going to fit a new one tomorrow evening (with new belts) and save the hassle.

Thanks again, very helpful.