I'm having a weird issue with my 2004 EX. About 6 months ago I replaced the transistor for the rear A/C as it wasn't blowing any air, and that was resolved. Lately, the fans in the front were making a loud high pitched sound when the fan was on high. This would go away if you turn the A/C system off or turn the fan speed down. Just this past weekend though, it started making that sound, and I pushed the off button and it was still going. I replaced the cabin air filter, and that seems to have resolved the sound, but even when the A/C is turned off on the front dash, there is air blowing out of the rear vents. anyone have any ideas?