Comdial Unisyn phone system extension problem

[gromcal]

I added 4 extensions to a comdial system. The first 2 (13,14) worked fine. However extensions 15,16, etc do not connect properly. One gets power but no tone. The other gets neither i re-punched these down numerous time. The diagram says that up to 20 or so i believe can be hooked into one trunk (cable from system to patch panel). I did not configure the system so it is possible they these extensions are not setup or disabled in some way?
(Each extension requires 2 pairs of cables.)
Thanks!

 

[ravnz5]

Is it possible the KSU is a 616 but that you may have to add another card to get to that configuration? Or, Is it a 308 KSU and you have to upgrade to a 616 KSU?

We all need a little help once in awhile. Tony the Phoneman..

 

[gromcal]

I on the side of the box it said TS616 i think. Revision D.

 

[ravnz5]

Although it says it is a 616 does not mean that it is equipped for 6 lines and 16 stations. This being an older phone system, and I've sold a few of them myself, doesn't mean that the 2nd card was installed to bring it to a 616 configuration. You should punch down a jack at the MDF on one of the extra station ports directly and plug a phone in to see if it works. It is my experience that you will need to add that 2nd card

We all need a little help once in awhile. Tony the Phoneman..

 

[gromcal]

Thanks for your great advice. I do have 2 questions. Extensions 10-14 work fine but not 15-18. Does that still mean its a missing card that is the problem? Also what is the MDF?

Thanks again.