1986 toyota mr2 interior lights is off

Since you're saying a few things are out, I'd say it's most likely a fuse. It seems odd that the tail lights would be wired with the interior lights though. The "alarm" tail lights probably work because they have been wired after the fuse box.

This link has a ton of manuals and scans for MR2s. http://opc.mr2oc.com/ The 1988 repair manual doesn't seem to have the fuse block diagram. The 1991 (MK2 model) repair manual does. (I'm not sure if the fuse blocks match). The other difficulty is that this car (1991 anyway) seems to have three fuse blocks. One in the engine compartment, one by the drivers feet, and another in the "trunk." Good Luck!

Before you start looking a the fuse box, make sure of 2 things: do you have power and a good ground at the light housing. Then, make sure that the door switches are grounded good, and are actually working. If no power, get back to me and I will get you to the fuse box, altho I doubt that the fuse box is the root cause.