Can't hook up the Plantronics 320 with my Pantech phone . Is the pass code 0000 ?

For all current Bluetooth headsets the passkey is 0000 (four zeros).
If the phone does not accept this code, please refer to your cell phone user's guide to ensure the proper setup procedure.

Note: Powering your cell phone off and on sometimes corrects this issue. You cannot change or personalize the PIN code/password of the Bluetooth headsets. It will always remain four zeros.
There is a link below to the Plantronics 320 User's Guide which may help you also.
Plantronics 320 User's Guide


Good luck from Headsets Direct!