Hey,
I can probably help. I'm presuming you have GPS software loaded onto the SD card slotted into the top of the iPAQ. Is it TomTom software - you can check this either by clicking on "Start" and "Programs" or by "Start", "File Explorer" and "My Device" then "SD Card"?
Have you got the TomTom car kit? You should have a lead to go to the cigarette lighter which plugs into the left hand side of the holder for your rz1710. You will also have a GPS device with a lead which plugs into the right of the holder. Slot in your PDA and plug the power lead into the cigarette lighter.
Turn on your PDA and double-click TomTom. The light to the holder should be green. After a few seconds (up to a minute) the GPS device will have a blinking green LED. This shows it is picking up satellites. Tap the screen and you will see the option to "Navigate to". Enter your destination city, street and house number! Away you go!
Two web sites of use -
www.hp.com and
www.tomtom.com.
Any questions just ask!