MECS-II is the Mazda engine management interface that was in place on most Mazdas up until 1996 when they switched to OBD-II interfaces. The MECS-II lets you get diagnostic info from teh ECU without a scantool etc and it can be quite handy
Refer this page for more...
http://home.golden.net/~trinity/Probe/malf/malfcode.htm
Kitty's 1994 BA has a MECS port as described
A.