Eco mode button

Hi folks. As a recent "new user" my PHEV 4H is suiting me fine. However, I have seen a number of posts here and elsewhere referring to Eco driving mode. There seems virtually nothing in the drivers handbook, and no chat explaining why the big button has been put on my dash. What does it do? When do I use it?

It will restrict your acceleration level and reduce the power of your air conditioning - hopefully to give you more EV driving.

KenMason said:

Hi folks. As a recent "new user" my PHEV 4H is suiting me fine. However, I have seen a number of posts here and elsewhere referring to Eco driving mode. There seems virtually nothing in the drivers handbook, and no chat explaining why the big button has been put on my dash. What does it do? When do I use it?

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We are fairly convinced it puts the car into front wheel drive mode too and cancels out the rear motor.

...not to mention turning you into the smoothest driving chauffeur in the process.

I mostly use eco-mode, but I have to admit that I'm a little worried about driving around using only one motor - I mean, won't it wear out faster?

Thanks

Having posted the question, I have found the earlier feeds ref Eco mode and the conclusion that it's useless and Mitsubishi should replace it with an EV only button. Sorry to look foolish there, typical to find the answer after asking the question !

KenMason said:

Having posted the question, I have found the earlier feeds ref Eco mode and the conclusion that it's useless and Mitsubishi should replace it with an EV only button. Sorry to look foolish there, typical to find the answer after asking the question !

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Hmm, not sure about this.

The PHEV is EV already when fully charged except when performance is needed, or the drive battery is depleted.
So why would you want/need an EV button? It's pointless.
There's also a technical reason for it - Li Ion drive batteries hate being stressed so the PHEV brings in the ICE to reduce the duress.
If we ran only on EV at times of high performance demand we might need a new battery like the Leaf is likely to.

With Eco mode, Mitsubishi have put their own stamp on the plug-in hybrid and set it apart from the rest.
It's EV only in eco mode (again until the drive battery is depleted, or you need more power).

Battery-save lets you choose to use EV later on in your journey (and in an understandable way).
For someone who lives a fair few miles away from London this is pretty useful!

It was an intelligent question - you didn't look foolish.

I like the PHEV just the way it is. If they put an EV button on it in future so be it, but as it is, it works for me. It makes sense and I use it.

Regards

We are fairly convinced it puts the car into front wheel drive mode too and cancels out the rear motor.

Click to expand...

Not me - seeing that Mitsubishi tells us it is a permanent 4 WD with the rear motor always powered up, although it may not be contributing much in certain situations. The anti-yaw system, for one, needs permanent power on all wheels.
If there is no arrow showing to or from the rear wheels it does not mean that the motor is shut off. It means that the power flow is neutral at that moment. If the motor were really shut off it would need a clutch to disengage it to prevent dragging.
It can easily be proved too. On a slippery road at speed stabilize the car so that the rear wheels are idling, so no arrow. Then give the steering wheel a flick left-right and you will see the arrows flicker and feel the rear wheels bite. Don't try this unless you know how to control a skid on a heavy automatic 4WD, though.

Much of the time at relatively high speeds, it is running in effective 2WD mode irrespective of the ECO setting. In fact it spends significant amounts of time running as a FWD petrol only car at speeds above around 60mph. There's nothing wrong with this - the electric transmission means that it can switch to 4WD in a fraction of a second if required. It may well be the case that, as jaapv says, it maintains a trickle drive to the rear wheels to negate drag, but that is not really 4WD.

It may be a matter of pedantic definition, but it is running in 4WD mode all the time with the power distribution favoring the front wheels up to 100%, depending on load and speed. If this were not the case and the rear actually switched off to be a 2WD there would be a drag from the permanently coupled rear motor.
Eco has indeed nothing to do with this. The ECO button modifies the accelerator response and heater system parameters.

KenMason said:

Having posted the question, I have found the earlier feeds ref Eco mode and the conclusion that it's useless and Mitsubishi should replace it with an EV only button. Sorry to look foolish there, typical to find the answer after asking the question !

Click to expand...

Agreed 100%

Lots of "4WD" cars (eg Honda CRV) have a viscous coupling and so spend 99% of their life as 2WDs.
This should in theory also save you money on tyres shouldn't it - arent permanent 4WDs more heavy on rear tyres?

jaapv said:

We are fairly convinced it puts the car into front wheel drive mode too and cancels out the rear motor.

Click to expand...

Not me - seeing that Mitsubishi tells us it is a permanent 4 WD with the rear motor always powered up, although it may not be contributing much in certain situations. The anti-yaw system, for one, needs permanent power on all wheels.
If there is no arrow showing to or from the rear wheels it does not mean that the motor is shut off. It means that the power flow is neutral at that moment. If the motor were really shut off it would need a clutch to disengage it to prevent dragging.
It can easily be proved too. On a slippery road at speed stabilize the car so that the rear wheels are idling, so no arrow. Then give the steering wheel a flick left-right and you will see the arrows flicker and feel the rear wheels bite. Don't try this unless you know how to control a skid on a heavy automatic 4WD, though.

Click to expand...

Yep, fair enough jaapv. I've just re-read what it says about the Eco-button on the Mitsibishi website and it says "4WD eco-mode"
It does handle differently though. Not the same as in Normal mode.

Thanks

My 4 month and 2500 mile experience, limited compared to some of you'll has shown me and this is my observation only, that there is very little noticeable difference between the two modes.
I carried out the same journey each for a week in normal and then in eco. I found very little difference in the miles i got out of the battery or in normal performance.
I did not use any 'pedal to the floor acceleration' nor air con so cannot comment about the difference of these.
I cannot replicate the traffic conditions or the exact weather but they both were similar in each week.
I think the eco button is just a compliance feature that Mitsubishi have thrown in.
I welcome comments.

Jazzenator, I have to agree. I can't note any difference in performance whether I have "Eco" mode on or off. Maybe I'm just naturally light footed anyway. Perhaps it might reduce the air-con performance, but what's the point? If you need air-con, you usually need every bit of cooling it can provide, I find.

I've tried doing trips with, and without, to see if I can notice any difference.
Usually the return leg, in the hope that there might be enough range to get back home on battery.
Without proper measurement, I haven't really noticed any difference so far.
The only time I do notice, is when I'm in a hurry to take my boy to one of his evening clubs, and he pushes the button while I'm trying to turn out of the end of the road, to join traffic, and the car suddenly feels like I've not taken the hand break off properly.

ECO mode does two things:

- Reduce the power consumption (and effectiveness) of the A/C (not the electric header, just the A/C).
- Remap the gas pedal a little bit.

Nothing more. The last could / should reduce the number of times you accidentally start the engine by pushing to hard on the gas pedal. But nothing you couldn't control yourself by being gentle on the gas pedal.