Volvo: 1989 760 check engine light reset, rubber plug, couple of minutes

Question
My 1989 760 check engine light always stays on for a couple of minutes after starting the car before going out. I was told by the previous owner that it comes on after a set number of miles to remind me to go in for service. Since the car is old and I'm doing most of my own service, I'm just interested in resetting the light so it doesn't come on again for a few months. How do I do this?

Answer
L Robinson,
The check engine light indicates a fault in the fuel or ignition control unit. You need to have the codes read and repair the fault then the light can be reset. If you want to try and just reset the light, disconnect the battery for 5 minutes. When the "Check Engine" Light remains on all the time. The "Service Light" stays on for two minutes and goes out. That is reset by pushing the small button that is in the instrutment cluster. It could be coverd by a rubber plug.