Where to start looking? I will first check the gas cap per the owner's manual. After that I'm lost. Most probable cause? So far it seems to run just fine. the car is a '98 V90 with 102K miles. Any help appreciated in advance.

Use your OBD (On Board Diagnostics) to get a code or codes then see where the codes point you. This is the standard fault finder built into the car. Quite a bit of info on the Brickyard FAQs on how to use the OBD and someone may be able to point you in the direction of a reasonably priced reader for the Diagnostics. First try resetting the OBD to negate any codes that have appeared. Then use the car and see if codes return. How is Hawaii? Nice and sunny I'll be bound! All the best, Peter. :car-smiley-031:

Thanks, Peter, for pointing in me right direction. I really love this car (bought 6 mos. ago) but have not invested the time to learn it as well as I should. Hawaii? Well, living in paradise is something that somebody has to do. Guess it might as well be me? The weather is pretty much perfect. My house has neither heating nor air conditioning systems and needs neither - we get moderate sea breezes most of the time. I see you are from Wales, cool. My relative from the 'old country' that most recently arrived in the states was a Reese Watkins from Wales. Was a coal miner over there and crossed the Atlantic in the late 1840s to move to Kentucky (where I was born) where he (your guessed it) became a coal miner. He fought in the American Civil War for the Union (North) with the 14th Kentucky and was in Sherman's march to the sea, and involved in the battle of Kennesaw Mountain where the 14th was commended for bravery by Sherman. He was my paternal Grandmother's great grandfather. He also had genetic predisposition to coronary disease which runs like a freight train through my family. Anyway, we were all over in Wales summer before last, enjoyed it very much. Lovely people and country. Cheers!

Update: removed and replaced the gas cap. Disconnected the battery just long enough to clean the posts and connectors. Light did not return. (so far).