I have a 2008 300C SRT8. In my old 2006 300C the EVIC had a working digital speedometer. The new one has a digital speed readout but it is non-working. I checked it one day and it read 30 mph fixed. Another day when I checked it it read 71 mph fixed. Is there any way to get it to work and if not, what does it display? Regards, Bob.