You have it right:

Power down of course.
Replace module.
Power up.
Check and test.

Just remember, if you're pulling out a 171 (which has caller ID pass-through support of either of the first or second port on the module, but not both) you must replace it with a 171 for that functionality to continue. If you install a 171 in place of a removed 170, everything will be fine and continue to work as it should.

 

Pat MacKinnon
Omni Telecommunications Inc.,
London, Ontario, Canada
 

171's are like unicorns down this way....!

Thanks for the help, but replacing the module did not help the problem and the new module did not load any data when replaced.

Let me start with the problem. There is a data type noise on on the first two ports on the second expansion module. I placed a jack on the the port and remove the station wire and the noise is still there. Figuring the next is the module. When I replaced it (power down,replace, power up)the noise is still there and the programming was gone.

Any help would help.

 

through the speaker while the phones on the hook?

very very low through the speaker. But when you press a digit to silence the dial tone you hear it clearly.

ksu  

Are you saying the whole KSU is bad?

or wiring issues got a spare ksu to slave in?

No spare KSU, I work on the newer systems. Any clues on wiring. I disconnected all the station cabling from the system but still have noise.

  

Are you sure that's not the background noise when BGM is turned on at the set on but no music is on the channel?

Leave the phone on the hook and just briefly press the digit 1, does the noise go away?

Incidentally, there is no programming to load into any of the 816/1232 modules. The station expander has no RAM nor ROM, only a few ASICs and 8 sets of identical support circuits.

If you disconnect all other sets and station wiring from the 170 module and connect only one digital phone right at the field, does it work? If so, do all 8 digital ports work?
(remember, the first digital port is on pair 2 and every 3rd pair upward. (2,5,8,11,14,17,20,23) You only need the one pair from the digital port to the 2nd pair on the jack to run a 72xx or 74xx station.

A short on any digital pair will knock out the entire four in a sequence. (1-4, 5-8, 9-12, 13-16, etc) The symptom is usually the other three phones tick and their LEDs flash very briefly as the sets try to boot but then everything dies again. They'll cycle through this forever until the short is removed from whichever station cable or set in the block of 4 has the fault.

 

Pat MacKinnon
Omni Telecommunications Inc.,
London, Ontario, Canada
 

make at least earth grounding