[ As seen the output shaft of the typical motor in the video is at a right angle to the axle of the DC motor inside it. My motor has the output shaft (after reduction gears) parallel to the DC motor axle. I
You are right to draw attention to this, and the picture.
So, are you sure it is a wiper motor? It certainly doesn't look like one, and questioning that will not only go quite some way to explain why you are having so much trouble with it, but also eventually explain any surprises you might get when you finally succeed - or fail.
I have never worked on a Japanese car but I don't imagine them to be any different. I don't recall any wiper motor not having a right angle drive i.e. a worm drive. There are three glaringly obvious reason for wiper motors to use worm drive.
1. It substantially increases the torque available from a small cheap motor
2. It reduces the speed to what is needed for the job i.e. not very fast and a hell of a lot slower than what a DC motor normally delivers.
3. 1 and 2 above are achieved with just two components - the worm, integral with the motor shaft thereby not actually qualifying as component, and the large gear wheel. The alternative is a multi-component gear train - with the attendant cost, space, and reliability issues.
Further, that motor looks pretty big for a wiper motor. Further still, I see talk of 25A but I have never known a wiper requiring anything bigger than a 15A fuse, and that is quite often shared with something else. And while you are at it, window motors are the same, for the same reasons - with the added advantage that the worm drives fits in the door better.
I think it is sort of actuator. I have no idea what for. Actuators on cars are usually vacuum. The most interesting thing about it is that your neighbour can't remember what car it came off (if it actually came off a car). You could find that your best solution is to go to a junk yard and procure what is definitely a wiper motor - one that is actually connected to wipers.