This is my first post so please bear with me.
I just noticed on my way home from work this evening that my battery light on my 1998 XK8 is faintly on all the time, even when the ignition is switched off. The brightness does not seem to change regardless of what I have turned on when the car is running either. The battery is about one year old and for cleverly months the car was off the road but was permanently hooked up to a trickle charger/battery conditioner.

does anyone have anything to suggest please

 

I would disconnect the alternator to isolate it from the car.
If the light goes out, you probably have a regulator or diode fault in the alternator?

There is a 'power-stud' on the right side of the engine compartment to the starter/alternator circuit that would be easy to disconnect.(main power to the starter/generator)

 

thank you. I will give this a try hopefully at the weekend. I assume if the light goes out then I need a new alternator?

 

Yes, unless you can find an automotive electrical shop.

they are getting rare.

They would be able to test the alternator and just replace the diode(s) that are bad.

Z

 

Always best to have your factory alternator refurbished with the proper Denso kit. No aftermarket worries if you do so....

 

Its a diode fault ...they all show up as warning light abnormalities ....new diode pack or new alternator.