Did you know you can get free map updates for your Jensen JRV-215?
Pull out the microSD card in the unit and put it in a PC--it should show up as a drive (in my case I have a laptop that has an SD card slot and I have a microSD to SD card adapter).
Then go to the Naviextras website
, create an account (its free), click on "get free updates", and on the far right will be "quick links" click on "Download Naviextras Toolbox".
Install the toolbox and run it. It will pretty much do everything automatically from that point on (it will find the SD card in the computer, identify the radio, find all available free updates, etc.).
When that is all done simply put the microSD card back in the radio and you're done.
Just did all this for ours (its the 2nd update I've put on it since I put the 215 in the Axis).