Warning icons I don't have a manual, so I need to know what this particular warning icon is

The light should be an icon. Check your owners manual for this icon

if the battery is reading 12.75v while running your alternator is bad
if its reading 14.50 its charing
if it is charging sounds like you have a bad ground to the engine wiring harnes

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Hello, "arthur o'neill".
Your car has parts under the hood to engage and control the throttle.
Those parts, as well as others, such as the speedometer,
and its cable must all be working properly,
for cruise control to work.
Either take it a mechanic, or get a 'shop manual',
for your particular model.

Year make model engine size?

Check your owner's manual or at least try to describe what the icon looks like. what kind of solution were you expecting when you just tell someone there's an icon in your dash you don't recognize?

The light will have an icon too, if the icon shows square shape rectangle with + and - symbol then its for battery, ((!)) is for hand brake and a small engine shape is for engine. You can find the images of these icon on Google as they are almost same on all cars. PS: Don't drive the car when these lights come up on dash and show your car to a good mechanic immediately.

Hmm... Does your Audi have the old version of the Tire Pressure Monitoring System? (I am guessing because it sounds VERY much like the 'icon' display that GM uses for warning the driver that tire pressure is low (or too high). Otherwise, ignore me...

It's similar, but not identical to the standard brake warning light (these usually have two circling arrows, one on each side). Check your brakes. The park brake may be on, or there is a fault in the brake system.

I think it's time for a rule requiring warning indicators to have a printed label as well as an icon. Too many people have trouble figuring out the hieroglyphics, especially when they don't follow a standard. Even if you don't read the language, you can look up the word on Babelfish. You can't do that with an icon.

maybe low gas indicator or check engine lite . i dont understand where you saying it is

It depends on what warning light is on!
In any case, from your description and experience, it would be your engine 'Oil' warning light: it comes on when there is not enough lubrication (thus the overheating) flowing because of low oil pressure: immediately check your oil leveland top up as required) and make sure that change your oil and oil filter as soon as possible as it is a very damaging condition and the engine could seize.
Hope it helps: let me know hoe you go.