Speaking from experience, the best way to prove this out to the customer is to put a tech on site and test directly to a test set/butt set at the block, with the line disconnected from the PBX side. If you see the 600 indicating it is ringing the port, nothing else will prove it except someone on the other end actually hearing the ring from the line.
I have to agree. The only way to prove if there is ring voltage coming from the TA616 is with a butt-set or volt meter, measuring the line without the PBX connected.
The fact that the customer's handset has a flashing light of some kind to indicate an incoming call, and this does flash, makes me believe the PBX is receiving and recognizing the ring voltage from the TA616 but is not then generating the ring voltage or passing it through to the customer's handsets.
I have a customer that today stated they have no incoming ringing on their PBX, but they see their handset flashing during an incoming call. I do see the line RA sig and RB sig show 1 when I call their line.
I suspect customer PBX issue, but are there any tests that I can run to confirm the TA616 is outputting the ringing to the customer's PBX?
If the PBX gives both an audible ring and a lamp flash, and the lamp flash is working, the problem must be in the PBX. The same AC ring voltage sent by the Total Access is used by the PBX for ringing and triggering the lamps.
I see that you're using E&M wink. As good practice, particularly when FXS and/or FXO lines are in use and even more important with E&M and/or ground-start lines, ensure that the grounding stud on the Total Access is connected to earth ground, preferably to the same ground bus as the incoming telco protector and the customer's PBX.