What kind of phone are you using? A lot of time "unapproved" phones can cause the Assist/bluetooth module to lock up. Brian is right, you can disconnect the module from power for about 10 mins then reconnect it and this will usually restore functionality but if the phone is not compatible with the car it is likely to happen again.
the module should be behind the left side trunk trim panel (Driver's side USA) you could also Disconnect the battery and shunt the cables together for about an hour to accomplish the same thing if you're not comfortable removing the assist module.

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DT

• Bluetooth issues - clow77 2008-10-05 15:22:50 (141 views)
  • Try disconnecting the BT module, and reconnecting it - Brian 2008-10-05 19:20:37 (108 views)
    • Re: Try disconnecting the BT module, and reconnecting it - clow77 2008-10-05 20:41:19 (100 views)
      • Well, it varies depending on which car model you have... - Brian 2008-10-05 21:14:15 (93 views)
        • Re: Well, it varies depending on which car model you have... - clow77 2008-10-05 22:49:38 (95 views)
          • It sounds like you have the Assist module-- I am not as familiar with those - Brian 2008-10-06 07:06:24 (112 views)
            • Re: It sounds like you have the Assist module-- I am not as familiar with those - dtbimmer 2008-10-15 23:34:25 (84 views)