Does anyone have a guide to replacing this thing? I've been digging for 2 days and so far my best guess is that the horn relay is on the back of the interior fuse panel. Looks like that will require removing the dash cover and a bunch of other stuff (why the hell would anyone ever mount something that needs to be replaced on the BACK of the fuse panel?).

I'm doing this because the horn doesn't work and I need to verify the relay before I check the clock spring, etc. I've already verified the interior horn/security fuse is fine, also the horn fuse in the engine compartment. Both horns work fine when connected directly to the battery. The steering wheel horn button just does nothing, doesn't matter which position the wheel is in (turning right/left, adjusted up and down).

Had a similar problem on my Matrix, took the horn cover off, checked the contacts, etc., still no horn, but worked connected from battery. I snipped off the female slide on connector and crimped on a new one and BINGO .. horn works! Go figure.