Don't know what you're working on but it sounds like you have accidently disconnected the speedometer cable from the speedometer. Check it out.
change the light bulb
This all depends on the package that was installed or the after market installation. The mp3 player is an optional item and could be installed or not.
Check your fuse it happen to me
Yes they can be installed in any car or truck that has a good battery.
No it does not.
To get a basic CD player installed in a vehicle, the price varies depending on the vehicle and the type of CD player. The cheapest options would probably cost around $25.
you probably installed an old one or just didnt complete the setup
no you need a flash player installed
Check ground wires... and all connections.
yes if you have windows media player installed
Make sure you have windows media player installed
You don't. However, it does come with HTML5 and QuickTime installed.