EV button confusion

MadJam250 · November 10, 2018

Recently bought a CT200h. ..loving it but can't really understand why there's an EV button when the car automatically goes in to EV mode when conditions apply anyway. Can anyone shed any light on when the button is used as a 'forced' manual alternative to the car's own automatic intuition please?

And why is the EV button the same shape and size and placed next to the Park selector button?! (Or, rather, why didn't they place the Park button somewhere for easier differentiation). Couple of times now I've almost accidentally selected 'P' instead of 'EV'!

steveledzep · November 10, 2018

You may wish to sneak off your drive early one morning without waking your neighbours. 😊

Britprius · November 10, 2018

If you need to swap cars on your driveway without the engine starting from cold. Pressing the EV button will stop the engine from starting if used before it has started. This saves fuel and high emissions associated with a cold start.

It has also been found that allowing the engine to start from cold, and turning it off before it has warmed up can lead to a ruff noisy next cold start.

John.

rayaans · November 10, 2018

Not useful at all tbh.

If the engine is cold, it would start regardless and would deactivate the EV.

NemesisUK · November 10, 2018

4 hours ago, rayaans said:

Not useful at all tbh.

If the engine is cold, it would start regardless and would deactivate the EV.

Not if you press the button before the first start in the morning for example. Once the ICE has started you can't over-ride it until it is warmed up.

I find it very useful, convenient for a stealthy departure early mornings. Or for frightening pedestrians in car parks!

MadJam250 · November 11, 2018

Thanks for the explanations. Despite having an decent Battery charge EV mode hasn't worked first thing for me, probably due to the weather and demand on the Battery. I still don't get what the button serves as the system automatically goes in to EV anyway if there's enough charge (and under normal conditions)?

NemesisUK · November 11, 2018

I use the EV button all year round and can, without fail, move off my driveway without the ICE starting. One can also force the car to remain in EV mode in stop/start traffic in winter when it will start up to provide cabin warm, as long as the traction Battery has sufficient charge.

Pretty sure Lexus wouldn't have provided the button if they didn't believe there was a use for the function?

Still, it's a 'nice to have' (IMHO) but one can drive without ever using it, should one so wish.

Zotto · November 11, 2018

Another use of EV button is when coming home at late night avoiding to wake up neighbors.

rayaans · November 11, 2018

22 hours ago, NemesisUK said:

Not if you press the button before the first start in the morning for example. Once the ICE has started you can't over-ride it until it is warmed up.

I find it very useful, convenient for a stealthy departure early mornings. Or for frightening pedestrians in car parks!

Doesn't work. The cars just start the engine regardless.

The EV function should work automatically in car parks anyway

NemesisUK · November 11, 2018

1 hour ago, rayaans said:

Doesn't work. The cars just start the engine regardless.

The EV function should work automatically in car parks anyway

My experience is otherwise. I can sneak off my driveway any morning in EV mode. The only requirement is there is sufficient charge in the traction Battery and one presses the EV button before the ICE starts. I press it the moment the button illuminates after pressing the Power switch.

steveledzep · November 11, 2018

2 minutes ago, NemesisUK said:

My experience is otherwise. I can sneak off my driveway any morning in EV mode. The only requirement is there is sufficient charge in the traction battery and one presses the EV button before the ICE starts. I press it the moment the button illuminates after pressing the Power switch.

Me too. There are other requirements also. Driveway needs to be level or downhill and only featherlight touches to the accelerator or the ICE will kick in.

NemesisUK · November 11, 2018

2 minutes ago, steveledzep said:

Me too. There are other requirements also. Driveway needs to be level or downhill and only featherlight touches to the accelerator or the ICE will kick in.

It does require a very light touch on the throttle. My driveway isn't flat and being gravel can cause the car to bog down but a gentle right foot can still move it off. Similarly at the junction of my road and the major road. The junction is short and steep but it's still possible to stay in EV and climb the incline. Definitely easier in the warmer months!

From my handbook -

Switching to EV drive mode when the gasoline engine is cold
If the hybrid system is started while the gasoline engine is cold, the gasoline engine will
start automatically after a short period of time in order to warm up. In this case, you will
become unable to switch to EV drive mode.
After the hybrid system has started and the “READY” indicator has illuminated, press the
EV drive mode switch before the gasoline engine starts to switch to EV drive mode.

colin79666 · November 11, 2018

Works for me when swapping cars round on the driveway. Also use it when stuck in stop start traffic to prevent the ICE starting just to run the cabin heating.

MadJam250 · November 12, 2018

Thanks again to all.

DanD · November 21, 2018

I have found that, if you switch the air con off temporarily, the car will stay in EV mode much longer. I sometimes do this when I am in the car waiting for one of the kids and want to listen to the radio without the engine kicking in.

NemesisUK · November 21, 2018

Would switching to Eco mode give a similar run time but with at least some level of climate control?

Farqui · November 21, 2018

Turning the cabin heater temps down/right down will keep the car in EV mode for longer.

ColinBarber · November 21, 2018

6 hours ago, DanD said:

I have found that, if you switch the air con off temporarily, the car will stay in EV mode much longer. I sometimes do this when I am in the car waiting for one of the kids and want to listen to the radio without the engine kicking in.

Turn off the heating system and just use the seat heaters, that way petrol engine won't cut in just to keep the coolant hot.

NemesisUK · November 21, 2018

41 minutes ago, ColinBarber said:

Turn off the heating system and just use the seat heaters, that way petrol engine won't cut in just to keep the coolant hot.

Quite high consumers, surely? Wouldn't they deplete the traction Battery quite quickly?

Britprius · November 22, 2018

13 hours ago, NemesisUK said:

Quite high consumers, surely? Wouldn't they deplete the traction battery quite quickly?

Not as high as as you may think. The heaters are rated at about 40 watts at full power. The traction Battery has a usable 1.2 kw at 288 volts equating to a load of 0.27 amps to supply both seats.

John.