mtnbound

Hi all - I purchased a 2013 RX450h in May. Now that it's getting cold I've noticed that when I start the car I get a moderately loud "whirring" sound from the dash for the first few minutes after I start the vehicle. It sounds similar to a cassette tape being rewound or something. It seems to originate from inside the dash, behind the CD player and other controls. This only happens when it's quite cold out (below freezing or thereabout).

Has anyone else experienced this and/or know what's going on? Should I be concerned?

NateJG

It's the hard disk in the navigation unit warming up the bearings.

rxgs2011

My 2010 RX450h made some unusual noises when it was cold too. Mostly from vibration and stress on the car body as the car rolled down the road. Most of my noise seemed to come from where the headliner met the windshield. It sounds like your noise happens when the car is motionless. I noticed that when it was moderately cold, below 20 degrees, the climate control system turned on the blower fan at low speed, and directed the air to split between de-fog and foot. This seemed to happen anytime it was cold. When the car got warmer the defog mode was de-selected. I assumed there was some kind of pre-programmed logic to keep frost from forming on the windshield from occupant breath before the water temperature was high enough to heat the cabin. Your sound might be the blower fan running on low. See if your vent indicator shows defog/floor while this sound is happening. Maybe your fan motor bearing is going bad, if the sound is pronounced, otherwise it is probably normal. Feel the defroster vents to see if air is blowing out of the vents. If so it's the blower fan you are hearing.