My maintenance required light changed from green (slowly) to red. i am a few hundred miles overdue for an oil change, which i'm doing today- how do I reset that light? I believe the oil change factor is the reason for the light change, because it's happened that way before when I brought it in to be changed. To save $, I've started doing the oil changes myself, but have no idea how to reset that thing.  Also (in case it isn't due to needing an oil change) what might that light be indicating? 

A4 always requires adding oil before it is due for an oil change, but only a few hundred miles is excessive. I buy 5 qts when it is on sale. Do you notice any leaks in garage?

That is just your maintenance minder system, which helps you keep track of when your oil changes are due. It goes from Green, Yellow to Red every 7500 miles. To reset, just insert your key into the slot next to the Red window. It will then reset to Green. -hope I'm understanding you correctly.

The maintenance required light lets you know its time for an oil change. Once the oil is changed the light can be reset. The light will usually blink for a few seconds as you approach the 5,000 mile mark and then stay on steady as the 5,000 mile mark is reached or surpassed.

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It just means it time to change your oil. If it has been changed recently and you just want to shut your light off just hold down the trip reset button. While holding it down turn the ignition on but do not start the engine. keep holding the button down for approx. 10 secs. the light should start flashing and then go out. then release the trip reset button and turn the ignition off. and the light will be reset.

On the dashboard there is a button you have to push with your key,
Do this after every oil change

No the check engine light is only for emissions issues. If the oil change is very overdue (10000 miles overdue) then that can cause emissions problems and the check engine light.

It's simply time to change your oil. After you change the oil, push your key into that slot on your gauge and it will be green until next oil change warning. Don't know how many miles you drive, but about every 5 or 6 months you'll see it change to let you know.

You have to reset it by holding the button on the dash that looks like odometer reset button then turn key on while holding that button that will reset that light.

Maintenance Required is a light that comes on after a predetermined number of miles. For example, if the maintenance schedule Honda set for the car calls for an oil change at 3000 miles, a new fan belt at 6000 miles, and another oil change at 9000 miles, then the maintenance required light will come on every 3000 miles and stay on until it is reset by the dealer. Some people, especially those that do their own regular maintenance but don't have a way to reset the light themselves, find this an annoyance. But others find it useful and take their cars in to the dealer every time the light comes on, and they rest assured that all of the regular maintenance is always done on time.

What this light does NOT do however is signal that there is anything immanently wrong with your car. It is not a "Check Engine" light (that's the one you should worry about if it ever comes on), but merely a reminder for you to do preventative maintenance. That doesn't mean you should *ignore* it, per se, as you want to make sure you have your car on some kind of maintenance schedule, even if yours is not as strict as Honda's. But there is no need to panic.

it comes on after a certain amount of miles
look it over check all belts hoses brakes fluids
and check the timing belt if all looks good put your key in the slot next to orange light and it will goto green again if you don't reset it will goto red in a few miles but it is not the check eng. light just a reminder