Mercedes-Benz MHI Bluetooth Interface Module bot pairing with iPhone

kindly, i have 2007 mecedes C200 with

Mercedes-Benz MHI Bluetooth Interface Module , i tried to connect it with iphone 3gs and 4 but i failed

the

Mercedes-Benz MHI Bluetooth Interface Module can see the iphone and it appeas on the panle but when i tried to pair by clicking on sen/d/call the dialling start by 16 didgit number then failed (no phone) exists

any help?