jaguar xk8 2001

 

My light came on when the alternator wasn't providing enough juice to charge the battery.


What caused the battery to die in the first place?


If its a "Check Engine" light, you need to have the codes read.

 

+1 on reading codes,if you don't have a scanner try Advanced Auto they will read the codes for free, then post back here I'm sure you will get assistance.
Cheers

 

The normal condition of the battery for a Jag is 12.5 to 13.5 volts. When running with accessories on the alternator puts out 13.5 to 14.5 volts to maintain battery health. When the voltage on the battery drops to 11.5 or lower the electronic modules begin receiving erroneous voltage and start flagging DTC's. Around 10.5 volts the modules begin shutting down and the vehicle stops running.

As the other have said go and get the codes read, have them print out the codes they read. Once they have read them ask them to clear all codes. Don't be to alarmed if the list is long.

Once the codes are cleared drive it for a few days. If the check engine light comes back ON then have then read again and post those code numbers. The new code numbers will be any actual problem that may be occurring.