Should have come here first! 07 EX here. I was having parasitic battery drain, but initially thought it was a bad battery. My Optima Yellowtop died at 36 mos, and it was replaced by a honda battery. The poor reputation of honda battery made me just toss it for a new battery (17 months old), but the new battery lost charge within a day! I realized there was something else amiss, and this thread pointed me in the right direction.
I bought 3 of these relays, for $17 at the dealer, replaced all 3 in the engine compartment fusebox this morning. So far about 9 hours with the vehicle off, and battery is still at full charge. I believe there is something wrong with this part, and I'll be ordering a couple of spares. (Dealer wouldn't sell me more than 3)