If the 92'* are like the 96'* with respect to the MALL module, I had the same issue with my SSEi, and it ended up being a fault in the MALL module. It started with the lights not going on when opening the doors- only when turned on by the dimmer switch (previous owner), and one day ended up with the interior lights being stuck on- and not going off except when fuse 6a was pulled. After performing the mall diagnostics (in thread below) as well as talking to the previous owner, (at the advice of the gearheads as well) I bought a MALL from the junkyard, and it fixed the problem.
I found this thread helpful- as it lists how to test the mall module- as well as the different I/O'*, etc.
I'm sure a gearhead would have a much better idea of the issue, as well as whether or not your car has the same/similar MALL module.
I hope this helps