TankDonovan,
Ah, finally some questions on this forum I can possibly answer. There are several pausible reasons why the drivers don't work. I'll cover the ones I know, in my limited repertoire of experience.
First, the drivers could be bad. This is simple to check for by simply removing the wires and taking a Multi-Meter set to measure resistance (Ohms) and checking to see if there's any continuity and if there is see if you get a reading anywhere near the rating of the driver.
Second, I see that there are a couple of switches to adjust the level of the mids and tweeters. This is most likely the area of trouble with your tweeters. You'll want to try adjusting these while putting a signal througth the speaker and see if one setting does work. If none work, just do the same thing with the MM that you did with the drivers in the first check and see if there's any continuity with the switch. A little shot of contact cleaner/De-Oxit before this might take care of the problem straight away.
Third, you could have some bad components in the crossover, such as a bad cap that's preventing the signal from getting through or hindering it in the case of one of your mids. I'm not too sure about this, I'm afraid, but I think that if you can measure no continuity through the capacitor, then it may be bad (this appears to be the problem with a speaker I'm currently repairing).
Fourth, there could be something wrong with the wires and/or connections. You could just have an old wire connecting everything that's gone bad and thus no longer has continuity; this has happened to me before and is an easy fix -- just replace the wire. There could also be a broken solder connection somewhere along the line in the crossover.
One last possibility for the mid that is only working partly, with no signal going to the speaker, gently press the cone in linearly. If you hear a hash sound, then either something is wrong with the voice coil (rubbing) or the spider has come off and caused VC rubbing. In my experience, this has caused greatly reduced output in the driver.
I hope one of the above is the culprit and thus easily discovered and fixed. I especially hope that the case is not your drivers being bad, though that can still be fixed by a pro such as GordonW or any number of companies.
- JP