owner's manual confusion
 

Wipers failed on my wife's 2015 Fit. I consulted the manual, which showed that the No. 5 slot for the 30-amp fuse was in the engine bay fusebox. Wrong! No. 5 was an empty slot for a 5A fuse. The Honda dealership could not figure it out. I finally found a downloadable manual which showed the fuse was in the box just ahead of the hood release in the left knee well. Go figure. All that aside, before I went out to buy another fuse, I was cleaning the wiper and let them slap onto the glass and, hey presto, they worked again. Any thoughts?

When you looked at the fuse, was it actually bad? Might have been a loose enough connection to fail the once though why the wipers hitting the windshield might have been jarring enough to reestablish contact is... well, it's hard to believe that's all it took. But I definitely would look to see if the fuse was okay. And I might even replace it anyway. They're cheap.

As with any mechanical system, corrosion or debris can gum up the works. If you park outside, especially under trees, or live in a high-rodent area you could have a bunch of leaves or other debris under the cowl where the wiper motor and drive arms live, which you could have jarred loose.

Or, you could have a bad connection or corrosion in the harness plug for the wiper motor (perhaps caused by the issues above). Again, sending a physical shock through the system might have (momentarily?) improved the connection.

If you've never been under the cowl of a 2015 car, it's not a bad idea to take a look and do some cleaning. At worst it will cost you something like 10 replacement cowl clips.

I appreciate the feedback. Will confirm fuse is firmly in place but also will replace it. Also, the car has been garaged since new. Fingers crossed. Still doesn't explain the discrepancy between her owner's manual and what's actually in the fuse box.

Having written my share of owner's manuals over the years, it's likely that what's in the owner's manual was what was on the design spec, which is what the creator of the manual had to use so the manual was printed and sitting in the glovebox when the car left the factory.

There must have been an ECO that moved the fuse location (or moved it for certain markets or certain models or whatever) that was not made an addendum to the manual. I'm not sure I've ever seen a version 1.1 or 2.0 of an owner's manual (though I sure would have liked to see one). Even getting an addendum to successive owners of a car would be a bit of a challenge.

I have received additions/supplements to the owner's manual for a couple cars. Most recently (a couple years ago), our 2014 Nissan Leaf received a small supplemental sticker for using the HVAC system with directions for where it should be inserted into the manual. I didn't bother as it was just some clarification (likely from lawyers) about when to use the defroster, which has always been pretty obvious to me.

A common failure mode for brushed DC motors is to get "stuck" when the motor stops in a certain shaft position. It's not a problem when running because the motor has enough momentum to skip over the bad spot in its rotation, though the motor might sound a little rough to a keen ear. Manually moving the motor (playing with the wiper arms) kicks it off of that stuck position until the motor stops there again by chance.
There's also a rotary switch attached to the output shaft of most wiper motors (the electric motor + gear box assembly) that lets the motor handle when to stop in the "parked" position. If the switch is failing, it may be able to find a position that is neither on the "running" or "parked" portions of the switch, preventing the motor from running. I expect such a position would be razor thin, or related to debris on or around the contacts. Again, that would mean jiggling the wiper arms could temporarily resolve the issue.

If the problem comes back and can be solved by wiggling the wipers, all of the above issues have the same official solution: replace the wiper motor assembly. It looks like the wiper motor can be disassembled if you want to take a shot at cleaning it, or just want to figure out what went wrong.