2000 vw jetta overheating, coolant doesn.t appear to be circulating thru engine

can be a clogged radiator,or a air lock in system or fans not working or top gasket blown.hope this helps

From this website:
http://www.obd-codes.com/trouble_codes/
You can click on the VW symbol to get VW unique codes.
Unfortunately, it doesn't give much information on the problem, except:
P1256 Engine Coolant Temperature Sensor Open/Short To Positive
So it could be a bad temperature sensor, or a wiring problem?

Hold the dealer accountable, for starters! It could be the thermostat, a coolant leak, a severe engine problem, who knows? You shouldn't have to concern yourself with diagnosing and fixing a car you bought yesterday, unless you bought it as-is.

VW family engine thermostat is behind the lower coolant inlet . It will be either a plastic or aluminum housing.

To find it...open engine lid and look down at bottom of radiator. You will see a rubber hose from the base of the radiator to the engine at the left side looking in. The hose is attached to the housing that holds in the thermostat.

FYI. Never run a VW engine without a thermostat in place or overheating will occur ....really !

It is called bypass hose. Attached here is the image. You can order on line from the website in the picture.

yes vw is very dependant on the cooling fan coolant pressure and expecially coolant mixture, check the gasket on the expansionbottle, as that can cause problems too, anyone of these will result in overheating

Get another boyfriend! "Just kidding"! ok, this is what I mean about "leaving it to the experts". #1 Make sure there is enough coolant, Check for leaks. Install a coolant pressure tester and check for leaks. Fix whats leaking. #2 Make sure coolant fans are coming on, and specifically at 220 degrees. If not, check fuses. Jump the coolant fan to make sure it comes on. if it does, then you may have a bad relay, make sure relay is commanded on. At this point , you may need a wire schematic for the coolant fans and related parts.

plastic impeller on water pump has come adrift

U'll need to bleed the system.

The thermostat may have stuck, replace it, don't overheat it again or you will blow the head gasket, that is VERY EXPENSIVE TO REPAIR!!