Had a Merlin Plus 820-D that had a bad feature module, replaced the module and everything is back up and working but the intercoms just ring busy when you try to intercom ??? Is that in the feature module ??? or program

I would guess the feature mod. The intercoms worked before they should work now. How is it with out the feature mod. Do the intercoms work.

Didn't try that,will be back in there friday and will try that, been awhile since I worked on one of these.

It's not going to function at all without a feature module. Do the ext's ringing busy have phones connected?

Is just a green light lit on control unit not red and green ?

With power off I would remove the feature module
carefully and put it back in and make sure its
fully seated and flush with back panel sometimes they are a little hinky going in.

1864, yes they do have phones connected,kenb,yes I do have agreen light,I did reinstall the feature model but I'll try it again in the morning, does it matter that the other FM was the smaller one and the new one has the busy buster,that's the only other thing that I can think of that's changed

You went from an 820d r1 to a rel 2 shouldnt make a difference.

How did you know it was a bad feature mod and not the box.

Was there any wiring done here the merlin runs on 4 pair ?

Take 2 phones and plug them directly into control unit and see if they work there.

the wiring has been in place for a "few" years, The system went down, replaced the feature modual and every thing came back up ecept the problem with the intercoms

Sorry for the misspells, watching the game at the same time, can't believe these guys, game 7 here we come :toast: :toast:

@1984: I thought certain features (at least with the 820D "breadbox" units) would work with OR without FMods...Intercom included. Perhaps this wasn't the case with the Merlin Plus units.

@DJG: I think KENB may be right regarding the box being the issue. Suppose an electrical hit took the thing out. Now suppose that the FM "did the trick" in regards to resurrecting most items. If Intercom doesn't work at this point, it's either got to be a bad FM or a good FM with bad registers on the main board (in which case, only a complete replacement will fix the problem).

Thanks for the input Dags, I was thinking a little that way too, I was going to stop by the shop in the morning, I have about 7 or 8 of them laying around but as always none have feature mods in them, we stoled them over the years for quick fix service calls, will see what happens, thanks for everybodys input so far

Thanks for the input Dags, I was thinking a little that way too, I was going to stop by the shop in the morning, I have about 7 or 8 of them laying around but as always none have feature mods in them, we stoled them over the years for quick fix service calls, will see what happens, thanks for everybodys input so far

I think there is some confusion here. the 820D is the merlin plus (the tall one with line cards for 4 COs each and station cards for 10 stations each)

The Merlin plus does not work without a grey feature card in the top of it.

The Merlin 820 (without the D) also known as the Merlin classic has 2-0 2-5 or 0-5 cards in it. It can work without a feature module but a feature module is required for the intercom to work. Only a Feature pack 2 will work in an 820 .

All of the websites do not mention intercom as a feature of the feature module but I remember that it was. I will check an old AT&T sourcebook catalog later in the day.

I knew there were basic features that didn't work without a feature card

from the users card:
"With Basic Service the CONFERENCE, TRANSFER, DROP, MESSAGE and SPEAKER buttons are not functional."

~SO~ intercom should work - it was the speaker key that I remember standing out as not working.

ttech, Yes it is a 820-D, Thanks for the other info, didn't get a chance to get there today,Had a few calls in the City first and took longer then I exspected, Monday I'll hit westchester on the way in, this way I can also play around with this over the weekend, I have a few 820-d laying around but no FM, but I can see how it will act without the FM at least, again thanks = Ken @Hitechcomm, 1864, KENB, Tim @ dagwoodsystems & ttech

You should replace the NiCD battery in the feature module and make sure you default the system using the programming defaulting procedure.

Just removing the battery should default the system

The battery isnt an over the counter item as it has 2 L shaped wires soldered on its ends
Its available from a Maine supplier .

Right now it seems you have a questionable feature module working in a questionable control unit ,All you 820ds laying around are quetionable. I would go there with some pretested working equipment as a place to start.