Cabin temperature in my 2009 RX 450H

[N13GEY]

On the drivers side, in order to get a cabin temperature of 19.5C I have to select at least 28C before the temperature increases. I suspect the thermostat, or..... Has anyone encountered this issue and have a solution? Thanks, Nigel

[Herbie]

If the passenger side works as it should, I can't see it being the thermostat because that would surely be common to both sides?

Possibly the mixer flap sticking or its motor going faulty?

Just sent you a PM that may help.

[DanD]

I used to have a 2009 RX450h. From memory, when you first start the car, it takes a few minutes before the heating kicks in. I believe this is to stop cold air from being blown into the cabin while the engine to comes up to running temperature. This is overriden if you select a high temperature.

Given that the temperature can be independently adjusted for right and left, I would assume that there are two thermostats, one for each side, but I could be wrong.

Not sure whether this is relevant to your question, but I seem to recall that the manual recommends that you should not select more than 3 degrees difference between the right and the left of the cabin. This aims to stop the two sides from 'competing' when one side tries to cool the car down, while the other tries to increase the temperature.

[N13GEY]

Hi Dan D. Your last para is probably the key! Will give it a go. Thanks a lot,Nigel