tweeter replacement

Help, I'm llooking at a bass extension cabinet by Ashdown Electronics but the tweeter doesn't work.

I'm trying to figure out how expensive this repair could be.

My questions are:
1, If the tweeter is ok is the problem just down to wiring? or could there be a more serious problem with crossover circuits? (I don;t knwo anything about speaker tech...)

2. Are tweeters ever so proprietary that they are impossible to replace?

3. How expensive can a tweeter get?

Thanks in advance!
Dave

I think you're talking about a Bass Guitar cabinet, correct? Which Ashdown is it? If it's one with the Blue drivers the tweeters can probably be replaced for $20 or so.