IPL Problem on AS/400 9406-170, V5R3 (I know it's an antique...)

I'm a young developer getting into IBM midrange for the first time
recently. I have an account with pub400.com, and that's proving very useful
in learning modern practices, and variants of RPG etc. However, I'm also a
collector (which is how I got into this in the first place), so I bought
myself a desk-sized AS/400 on eBay. I know it won't be terribly useful,
it's just a curiosity for me to play around with.

Hopefully this isn't considered an inappropriate topic for this list;
please let me know if it is.

I know it's in working condition from the seller, and he gave me the
QSECOFR password. I think I am doing the IPL correctly (I used mode A and
M), it displayed a lot of codes that related to mirroring disks and ran
fairly loudly for a while, and then dropped back to the "01 A M" on the
panel. Does that mean it has finished the IPL?

I think my problem is in connecting the terminal. The machine came with a
Praim VGA console box, which seems to start fine. It has what I think is
called a "T-connector" on it, I assume that both ports are equivalent? Does
the other port require a terminator or something like that? I have plugged
the Twinax cable into the T-connector, and the other end into a 4-port
"strip", PN 72X5645. This strip terminates in a D-sub, 8-pin connector.
There's two places to plug that into the system, a case-mounted port
labeled "MI", which leads to a jumper on the motherboard. The other option
is an adapter card mounted below. I currently have it plugged into the "MI"
port. Oh, and the Twinax is plugged into port 0 of the 4-port strip, and
all the twinax connections are tightly screwed in, not damaged, etc.

Also, what is the difference between Copy A an B of the LIC? Backup?

Thanks,
Doug Dunn