If you are experiencing a intermittent problem with B12 addon working on some 9508 and not others. I believe the problem is not firmware, but hardware. The short line cord provided by Avaya that plug on the the 9508. It's not a solid fit, in some cases.
There is one way you can be for certain?. The power supply 1151D1 is putting out about 48 VDC Pin 7 & 8 to phone. The Power out from 9508 module jack over to B12 add-on. It should light up if its receiving power. So, check to see if there is power coming out of the 9508. Plug the line cord that goes to the B12, into a splitter. Test voltage. Test voltage going in & voltage coming out.
I hope this help someone, it drove me crazy at first. A few postings read lead me to it.
There is one way you can be for certain?. The power supply 1151D1 is putting out about 48 VDC Pin 7 & 8 to phone. The Power out from 9508 module jack over to B12 add-on. It should light up if its receiving power. So, check to see if there is power coming out of the 9508. Plug the line cord that goes to the B12, into a splitter. Test voltage. Test voltage going in & voltage coming out.
I hope this help someone, it drove me crazy at first. A few postings read lead me to it.