Normally the "Service" light comes on at preset intervals, i.e. 5000 miles, to remind for oil changes. It usually will continue to come on for a couple minutes each time you start the car car until it is reset. This can be done by dealer with their tool, or a $200 tool from IPDUSA you can do it yourself, or you can place a piece of black electrical tape over that indicator as some have done....

The "Check Engine Light" indicates some fault has been detected by the OBDII system. '96 and higher require a OBDII scan tool to read code through plug under coin tray. Some auto parts stores around here (AutoZone) will read code for you for free (if the guy can figure out how to use the scanner!!) Can find meaning of code on several internet sites, or ask here for help.

For the Do-It-Yourselfer, eBay has a lot of OBDII scan tools listed. For a PC software and hardware interface solution you can try www.obd-2.com and www.scantool.net.

The obd-2.com one also lets you reset the service light on some Volvo's which is good, but program doesn't look very user friendly.

The scantool.net one is the cheapest I've found, especially if your inclined to build it yourself. The software doesn't do as much as the other one yet, but looks easier to use. Also lots of info on OBDII and user forum, etc.

I'm still looking myself. Thought Check Engine light went off by itself and then realized the bulb burnt out.... so now have another problem to fix!!