Which engine is in your Bug?
Is the coolant level correct? A mixture that is too rich in Antifreeze can turn the red warning light on... there is a level sensor in the bottle / reservoir
that "senses" fluid level, but can not do so if the mixture is too rich (should be 50/50 mix of antifreeze & water).
Check for correct coolant flow BACK into the bottle... at idle, you should see fluid flowing back in to the bottle:
Sample of incorrect flow:
An "electrical glitch" or the wrong fluid mixture / level will cause and immediate flashing of the red light when cold... a mechanical issue such as a broken
water pump, will not cause the red light to flash until the engine has run for some time.
Sample of bad water pumps:
Sunday, October 28th, 2012 AT 6:47 PM