Here's a good one. I have an SX-20 that keeps showing talk path faults on every other talk path. I've changed out the misc. card with a good one, but still get the faults. When I disable all the odd talk paths, then I can take stations off-hook without dead air. This only leaves me with 6 talk paths. Any suggestions (Other than switching out the CPU)
GEN. 503-07 software is good.

This can be caused by a station card also, as I recall.

Bare with me its been a long time since I've done any work on a SX20. When you replaced the misc. card did you reuse the trunk modules? Does it have the trunk expander board with 2 trunk modules?

Do you hold your breath when you power it down?

Found the problem. It was the CPU. It would not report with diagnostics any CPU errors, but when I replaced it, "POOF" it worked just fine. Kept getting AL 41, AL 21,22, etc. nothing indicating the processor. Thanks for the reply's folks.

Probably should have suggested that you pull and reseat every card in the cabinet1st. You might be surprised if you re-install the CPU. Reason? The contact fingers in the card slots are old and tired and dirty.

The CPU was definitely bad.