I have a 2001 S-Type 3.0; after installing a rebuilt alternator the charge light (red battery) would come on.
The regulator in the rebuilt alternator does not "play-nice" with the ECM so I replaced the voltage regulator in the rebuilt with one from a Jaguar alternator from junk yard....no more light.

 

clubairth1, no, I have never had any lights before on the dash prior to all of this.
Menasce, thanks for your help. I now have a new OEM, Jaguar alternator in my car.


An update: As of this morning. I now have my vehicle at the Jaguar Dealer. The local shop cannot find the source of the issue. When I crank the vehicle each morning, it seems like the battery is flat, I get all the usual lights and "fault" messages. I am hoping the pro's will figure it out. I am able to drive the vehicle but it feels like it is in a safe mode. After a few miles, I have to pull over and recrank the car. All the fault messages and lights go away with the exception of the Check Engine light and "transmission fault".

 

Scott;
I re-read this thread but I don't know how old your battery is?
Sorry if you have posted this.

You may have pushed the battery over the edge with the alternator failing.
.
.
.

 

tbird6- I purchased a new battery in late October, so the battery is about 7 months old.

 

Hey I am in the Houston area too! I use Momentum Jaguar because that's where Brutal works. I also request that he works on my car.

Which Jag dealer is your car at?

I am a shade tree mechanic and don't give up too often but the STR has had a few things that were just beyond me. I will say the Jaguar dealer has been able to fix everything I have requested.
.
.
.

 

If Brutal can't fix it ... the car is pretty much toast

 

My baby is coming back home tonight! Looks like the Jaguar dealer got it all squared away. Two things were the issue...
1) Bad Cell in the battery. (I will need to check my warranty on this one!)
2) Corrosion in the terminal for the alternator.
Thank you all for your help!