I have a 1999 S80 with 81,000 miles.The issues are this.At first a message came on saying the alarm service needed servicing.About ten minutes thereafter,another message appeared,which was in effect emissions system needs servicing.Thirdly,about ten minutes after that last message, the check engine light came on.

Now both messages are gone and the check engine light stays on.There is no apparent decrease in performance with the car or problems with the alarm system.

What 's the deal and what should I do?
Thanks.

I found the following on a website that showed me how to change the oil.
Intermittant (non-critical) faults show the orange (Service) light, Critical faults are red and show up on the mesage board
"you can rest your service light by; ignition key to position I, push in and hold the odometer rest button (use your left hand), move the ignition key to position II, wait until you see the service light blinking, then release the odometer rest button."

Get used to the warning lights. Consider them "festive". You may have something going on with your charging system...check out the serpentine belt for starters...and then get the charging system checked. Another thing that whacks out is the ignition switch/immobilizer, not a large expense, but an irritating one...but one of the first things affected by low charge is the alarm system.