I just purchased an aastra 9116lp and have no display

No it's an AC output adapter. 16 Volts AC. I thought it would be DC also but after looking at the output on the plug it showed AC. I measured the voltage and got 19 Volts AC. However I still can't get my display to work so I'm tearing the phone apart now to see.

A 9116 N has a power brick that needs tone plugged in to it. They are usually a black power brick. Without the brick there is no display If you are referring to no caller I'd. That is a function that you have to ask for from your provider. A blank screen usuall has a funny weak ring also. If you have a grey power supply look at the voltage on the brick if it say that there is ACvoltage output. It is not the correct one. You need to have a DC voltage output on that type of phone