No idea what would cause the problems in your case, some sort of interference, maybe ionizer? But ionizer should be mounted inside driver's vent? I use mine daily to track data that build in Nav won't have, like speed, altitude or save tracks and I have no problems whatsoever. I keep my Meridian in the center console cup holder, next to the shifter and everything works. I'm not sure if you're very familiar with GPS operations but sometimes there is a change in Sat configuration (for example clock goes bad) and it takes few minutes to upload new data to GPS, depending on the software the sat screen (the one showing position of all birds in sky) can go blank since previous data is not valid anymore. But I would imagine GPS worked outside the car in your case and stopped when brought into the car so interference would be main suspect here. I would also imagine you did check different locations, away from lock system transmitters and power button? Since it works in my car maybe your car has more electrical interference? Dealer as usual has no clue and is confused.