Why does the blue temperature light in a 2000 vw beetle turn from blue to flashing red?

Engine is overheating...not the correct answer. My 2002 does the same thing. I have had it to the dealer 9 times in a year. It is not over heating. They have replaced the sensor,heat pump,thermostat..still comes on. The dealer has not solved the problem in a year of visits.

I had the same problem with an '03. I took to the dealer many times, they changed everything, only when they changed the water pump did it seem to correct it. One time after warranty expired, even the check engine light came on, and a diagnostic code was issued that the dealer could not understand. After some research online I decided to change the water pump, timingbelt, thermostat, and temp control switch. I have done all at once, and not had a problem on that side since. (knock on wood)