hi Catymag, firstoff, apologies for mistaking you for a man.

This is a zumo 500 Unit and no option for using it as a gps reciever. I have read somewhere there once it goes into the diagonostic mode, if u plugged in the usb, cable, it will promopt u to install more usb drivers and then it works as a reciever.

In my case, it just takes power from the usb cable. unit works like a reciever. but if u took n route, then gps is missing. On the diagnostic mode, on the thrid line from the bottom, ( where it is written, usb device) it shows GCM20 ( as aganist no cable selected).
I am sure, the unit is not able to go into the usb mode.

Please advice me if u got any other option? Spanner option is not available for Zumo 500.

Thanks again for replying back. I live in india, and not many use gps out here. garmin support is not worth mention.

Looking forward to hearing from you.
Regards