I believe the MIL on a '93 would get 12volts with key on and pin17 on the computer will ground the MIL to light it up and unGround it to turn it off.
So test which contact in bulb socket has 12volts with key on, the other should be a ground just after key is turned on, and then unGround after computer finishes self-test.
As far as I know you do not have to Crank or start engine, MIL should just go off after a few seconds when self-test is done, if MIL stays on then there is a problem with self-test or a code is set.
Also check fuses in cab fuse panel, MIL will be with other devices not on it's own fuse, so if anything else isn't working it could be a fuse.
And bad connections on dashboard connectors is not an uncommon problem in older vehicles, good guess as to the problem.
Last edited by RonD; 07-21-2015 at 01:07 PM.