check engine and maitenance required?

Hey so i just got rid of my bad luck 90 accord ex and got a 94 accord lx 5 speed. So this is my issue. On my 90 it only had a check engine light on it, and that only came on if a sensor went bad or something, or at least thats the trend i noticed, but on my new 94 accord, it also has a maintenance required light, or switch. What does this indicate. Ive had the car for 3 weeks and when i got hte car the maintenance required light was green, and recently it went to yellow. I gave it a tune up (wires, plugs, oil, cap, rotor) and the light turned yellow after that. Any thoughts?

If it's like my '92, Then the light is just a disc that is connected to the odometer somehow. Even if you do the maintenance, the color won't change back to green. There is a button next to the indicator, and if you push that in with a key or something then it will change to green.

ok ill look for it, thanks