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Heat up a hybrid

I recently bought my wife a Lexus RX-400h. When she starts the car in the morning the engine does not start, it just runs off the battery until it needs the engine to charge up the battery. How does one warn-up this car? We live at Lake Tahoe and the winter temp. is in the 20s-30s and the car is cold in the morning. Does the heater run off the battery, so I can turn the key and the heat will come on or is she just stuck driving a cold car to work?

Also, I noticed that when she drives uphill the engine starts and charges the battery, even if it is not very low. Often, she is going back down hill within 10 minutes and it seems there should be a way to shut off the charging program if you know that you will soon be going downhill and charging the battery then anyway. Is there any way to ?shift into battery only? when you know you do not need to charge it?

My guess is the car feels it needs the extra power to climb the hill & kicks in the gas engine. Sorry I can’t help with the heater. I have a brother that owns a Prius but lives in AZ and rarely needs heat. I’ve often wondered how that works in cold climates…??

What happens if she turns on the heat while it is running on the battery? Does it just blow cold? If so, something may be wrong with the car.

The engine doesn’t just start up to charge the battery. It also starts up automatically if there is demand for extra power. Perhaps if she had a lighter touch on the throttle, the engine wouldn’t start up.

The heater blows cold at first. I guess my real question is does the heater get its heat from the engine coolant, and so the engine needs to run and heat up before it gives off any heat, or does it run off an electric heat strip so it should be hot right away?

Don’t know the lexus system, read owner’s manual for , hopefully , the answers.

Ford Escape hybrid will run the gas engine all the time when a/c compressor is required in; max a/c–defrost–defrost/floor modes.
They are shown in orange on the panel, the others are white.

------ To warm up in the morning we simply select one of the defrost modes and the engine stays on.

It gets heat from the engine, like a normal car. I think Ken’s suggestion below should work for you if you’re talking about trying to warm up the car before you drive it. Otherwise, I believe what happens is the first time the car turns the gas engine on, it will run until it’s warm before going back to creep mode.

Interior heat comes from the engine coolant, just like any other car. It’s not electric, and you won’t get any heat until the engine warms up.

If you start the car and immediately turn the heat on, what happens?

I’d go outside in the morning, open the hood, and have her go through various combinations of climate control settings to which on causes the engine to run.

I’ll try this tomorrow and let you know what happens.

I can turn the key and the heat will come on or is she just stuck driving a cold car to work?

Now that you have the car can’t you find this out on your own?

I don’t think there’s much point second guessing its operating routine, when the battery charges, etc.

I wanted to know how it is designed to work, so I can tell if it is working correctly.
I don’t think there is much point is posting a message about second guessing!

Well then, If you refuse to call it experimentaion.

See owner’s manual.
( 06 Escape hybrid manual told me the gas engine runs all the time in the three selections. Logic told me which to use to warm up the car. )

Ask techs in dealership.

Or google ‘highlander owners forum’, for very specific questions like this you need to be talking to either the dealer or another owner.

If I was considering buying one of these cars and certainly before I actually bought one I would have spent considerable time reading up on just how,when and why systems operate and in paticular since you live in a cold area, how the heating system works.

I can tell you how we warm up my wife’s Olds Alero…

We keep a small electric heater in it and plug it up on a timed circuit. It comes on an hour before she leaves for work and the car is toasty by the time she gets in.

No sense in burning a dollar of gas letting it warm up when a nickel of electricity works just as well.

And how exactly is your comment helpful?

Well now,
I don’t have a Lexus rx-400h owners manual to read.
I don’t have a Lexus dealer in this small town to ask.

But you do.

The owners manual is in YOUR glovebox, not ours…

I’m jealous. If your concerned, I’ll trade you one of my dumpy Toyotas where the heater works in a traditional way. Sounds like a great car. For that money, Lexus won’t leave you out in the cold. Run it like an ordinary car.
I’d be more interested in how well the awd function works in different conditions off the electric motors ?

Well now that I have read these many posts, just how does an electric (or hybrid) heaat up on a cold morning??