The PN is
76710SHJA01, about $60:
2005 HONDA ODYSSEY EX Rear Windshield Wiper Motor
1. Remove Interior Panel (standard screwdriver).
Just watch how things fit so you can re-install properly.
2. Remove Rear Wiper Arm Nut
(#5 in diagram).
You may need a puller to pull the wiper arm off.
3. The REAR Wiper Motor: make an accurate note of all the rubber grommets/washers
(items #7, 8, 9, 10, 11, and 12) so you know how to re-install them!
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