Well, after 31k problem free miles, the light came on during the am commute. I pulled over as soon as I could and checked the gas cap. Sure enough, it was loose (turned till it clicked). the OM says to go for 3 drives and the light should go out. If it doesn't, take to dealer.
Seems odd to me, what constitutes a 'drive'? I'll use the car some more in the next few days but I'm wondering if this is a big deal if the light stays on. I hate to bring it to the dealer for a light that stays on.
Any thoughts?
Thanks everybody...

 

Don't worry about it. It will go out when it goes out. You know why it came on, and you know it was no big deal.

In a day or two you will glance down and -- surprise -- it will be off again.

 

OR, you can reset it yourself anytime you want by pulling the "BACK UP" fuse for 30 seconds. That's wha the dealer will most likely do, but they'll do a complete scan and then charge you for an hours labour.

 

Thanks fellas,
XV, I have the Helms so I'll know which fuse to pull - hate to drive around w/ warning lights on.

 

Which fuse is it? Mine came on, I want to reset it.

 

IMHO, pulling the backup fuse for a loose gas cap is overkill. Just have a little patience.

Once you pull the backup fuse, you then are supposed to do the "idle relearn" procedure (shut off all aux power drains and let the car idle for five minutes + any time the cooling fan is on). You also have to redo the procedure to allow you to turn off the AC while in defrost mode (assuming you wish to do that). And your ECU will forget anything it has learned about your engine and your driving style.

All that because you were too impatient to let the light go out on its own. Your choice, but I would just wait for the light to go out.

 

Thanks Mike,
Wasn't aware of the full implications.

 

Well it's not like the world ends if you reset the ECU. But it just seems like way too much trouble compared to just waiting a couple days for the light to go out on its own.

If you didn't know why the light was on, or if it was on for some reason other than a loose gas cap, it would be a different story.

 

Technically, you have to go through three complete "cycles" to reset the light. A cycle is starting the car with a completely cold engine, running it at least until it is warmed up (usually around 3 bars on your temp gauge), then turning the car off and letting the engine completely cool down.

If you restart your car when the engine isn't completely cooled, it won't count as a new cycle.

 

I usually self service even at full service stations, making sure it clicks. This young fellow was excited about the S and checked the oil and rushed the cap while I double check the stick.
Lesson learned.
Fascinating how 'smart' cars have become...does explain 'drives'.