Palm OS Treo
1. Before you plug in the phone open the dial pad and type the following
2. For Verizon/Alltel, dial #*#3424# or #*#3424, Talk
3. For Sprint/Qwest, dial ##3424# or ##3424, Talk
On the Palm OS phone will say Passthrough Enabled, if the phone reboots, complete the steps again until you see Passthrough Enabled
Windows OS Treo
1. Before you plug in the phone try one of the following:
2. For Verizon/Alltel, dial #*#3424# or #*#3424, Talk
3. For Sprint/Qwest, dial ##3424# or ##3424, Talk
On the Windows OS phone you should see a white screen which will say DMR Radio Active or Diag Mode Active