Symbol on marine tachometer flashing

Hi,
it looks like your GPS has somehow reset to the marine locating function.
did you check the settings and go thru all the choices that may have been modified ?

By unit, do you mean the thermostat? And if so, do you mean the whole face is flashing, or just a heat or cool symbol? And if your talking about the heating/cooling unit, are you talking about a flash on the board?
A thermostat face that is flashing is usually batteries.
A symbol that is flashing on a thermostat indicates a call and is in a delay. There will be a 5 minute delay on calls if the call has been short cycled, powered off and on, etc.
If the symbol continues to flash for an extended amount of time, then the problem is in the furnace, air handler, etc.
If the system is working, but flashing, then it could be the programming of the thermostat.

What does the orange symbol look like? A Little engine? If this is the case then it is the "Check Engine" light. Please read on.

The information below was complied by me, it explains what causes the check engine light to come on and the process of finding the cause.

When the Check Engine light (or Service Engine Soon or small picture of an engine) is turned on, the systems computer control unit (called the PCM) has sensed a fault in the electronic controls of the engine and/or the emission system. When this happens you will seldom feel the car engine run any different. There are about 200 possible system faults (the gas cap is just one of them) that turn the Check Engine light on, to know what has developed a problem you must have the system tested, this is called an OBD2 fault code test, Kragen/Oriley and Autozone parts stores (USA only) do this testing for free.

orange would mean service engine, like the old orange colored service engine soon lights that are computer or emissions related. red would mean oil or engine problem. it's probably a motor symbol so we can dismiss ABS or other red brake light.

The 2009 Saturn Aura added the bluetooth (phone) feature and many other GM models with similar looking radios had it in past model years. The 2007 did not come with bluetooth (or Human Machine Interface).
There are two possibilities: the radio has been changed from another vehicle and is incompatible with your car or locked or your OnStar is malfunctioning. Either situation will require a trip to your friendly Saturn dealership (or Saturn Service Center) to repair.

This symbol means that your backup battery needs to be replaced. It is a "button battery", type CR1616. Instructions for replacing it are in the manual, which is available to view or download here.

if its yellow and on the tachometer side of the dash it means you have a burnt out bulb.

It's a low tire pressure warning light. Make sure the tires are properly inflated.

it means you have no back up battery installed to save time/date info. I know on the GL2 if you open the LCD screen there is another small plastic tab you can open and insert a relatively small battery. Do it and the icon will disappear. Otherwise its no big deal. If you dont need time/date stamps on your tapes then there is no need to install the battery unless you are just annoyed.