Volkswagen Repair: vw jetta glx 1997, jetta glx, protection circuitry

Question
... i replace the instrument panel cluster in 2005...because the speedometer and tach would not work...it has happen again in 2007...everything else works on the instrument panel...the dealership can not give me answer why..they also replace the panel in 2005.....any ideas...it just stop working...

Answer
This has not happened to me before.  However, it may be possible that there is a surge of power...either amps, or volts from the alternator that is not protected against in your car.  Do you have the original radio/stereo in the car still?.....Or, do you have an aftermarket radio with an amplifier, and subwoofer.  My guess would be that you have a stereo, a subwoofer, and an amplifier, and you are still using the original alternator, and no special surge/protection circuitry...Am I right?