Acc Warm Up Problem On '09 Rx450

PSB10K · December 15, 2015

Hi Guys,

I have recently acquired an '09 RX450 Premier which I love - but it takes ages (over 5 mins) for the climate control set on Auto to increase the fan speed about level 1, in spite of the water temp gauge showing warm to hot in quite a quick time. This is my 6th RX and they all warmed up and activated the fan speed much earlier than this car.

I took it back to Lexus Croydon under warranty and they apparently checked it, said there was nothing wrong with it, and that these larger engined RX's always take a long time for the ACC heating to get going. I frankly don't believe this!

I am having to use the heating manually which is a bit of a pain, and should be unncessary. Any help or feedback from RX450 users please?

Thanks,

Peter

PCM · December 15, 2015

Maybe take it off 'auto'?

RXJasonRX · December 15, 2015

Yes. Just take it off automatic. I think to an extent the system will learn your preferences the more you put them in. Mine seems to.

Sent from my Nexus 7 using Tapatalk

DanD · December 18, 2015

PSB10K... Mine does the same. I was told it is working "as designed" and that there is nothing wrong with the car.

PSB10K · December 18, 2015

Thank you Daniel,

A disappointing response from Lexus !!

PB

rayaans · December 19, 2015

It is working as designed. When in auto the air will be heated up to desired temperature and then blown through the vents.

When you take it off auto, all your doing is blowing out cold air and then heating it up again once hot.

PSB10K · December 20, 2015

Thank you Rayaan,

It's my sixth large engined Lexus albeit my first 450h, and still disappointing when all the others warmed up on Auto so much quicker. One would have thought that once the temp gauge showed 35% heat, the climate control would start to kick in - but no.

I guess I will have to just overide the Auto with manual control from now on.

Hopefully, Lexus will have sorted this out for the new series 3 version due out next month (although it will be some time before I could afford to upgrade).

Peter

RXJasonRX · December 20, 2015

I would have thought it's not a very important consideration as It Gets warm pretty quickly just enjoy the rest of the car

Sent from my Nexus 7 using Tapatalk

Parrot of Doom · December 20, 2015

I'd check that the air intake wherever the temperature sensor is isn't blocked with fluff.

rayaans · December 20, 2015

The AC is also run using the hybrid Battery.

Therefore it is important to remember that the AC takes much much longer to heat up if the car is in ECO mode compared to normal.

The 4th gen RX has a customize option whereby you can do just that i.e. have car in eco but ac in normal

Valkirk · December 20, 2015

This is perfectly normal (and exactly as it operates in my car) it is because you have the car in Eco mode, this maximises turning the engine off as soon as possible to save fuel, if it's cold outside it restricts the amount of heat the car channels into heating the cabin instead it emphasises keeping the engine at a temperature it can turn off easily.

This problem is easily and instantly resolvable by putting the car into normal mode, sometimes when it gets very cold I forgo the benefit of lower fuel costs and move into normal - instantly the engine fires up even when stationary and the heater starts blasting into the cabin.

So if you performance of your previous Lexus heaters then run in normal :)

PSB10K · December 20, 2015

Thank you Guys,

At last a logical response, which I completely understand. Why Lexus Croydon couldn't have told me this before bringing the car back under warranty is beyond me! I was in Eco mode, and now in Normal, and the heating now seems fine.

Peter

rayaans · December 20, 2015

Thank you Guys,

At last a logical response, which I completely understand. Why Lexus Croydon couldn't have told me this before bringing the car back under warranty is beyond me! I was in Eco mode, and now in Normal, and the heating now seems fine.

Peter

Glad it's sorted. Worth remembering that most salesmen don't actually know much about their products. 9 times out of 10 they only know enough to sell the thing

Valkirk · December 25, 2015

It amazes me they don't know more, they only have a very small range - they should be able to tell you everything about them, they tend to run them as their own cars and surely they have enough interest in the brand to read about them.

rayaans · December 26, 2015

It amazes me they don't know more, they only have a very small range - they should be able to tell you everything about them, they tend to run them as their own cars and surely they have enough interest in the brand to read about them.

Yes. My dealers are Stockport and Bradford. Bradford staff keeps shifting around from brand to brand so don't have much knowledge on the products. I don't really mind as I don't really need to ask them as I usually research on here.

Stockport on the other hand have staff working for 8 years or more so have a lot of insight into the vehicles