Mild Hybrid - lesson learnt

[AdamInKent]

This might be something that is obvious to some, but it has taken me a while to figure out, so I thought I would share in the hope that it might be helpful to one or two of you.

When AutoHold is enabled, the car holds the brakes when you take your foot off the pedal, but I was finding that there was inconsistency in whether or not the car would shut off the engine or leave it running. I have found, recently, that you have control over this (assuming that the car has not turned off the engine whilst slowing to a stop). If you brake relatively gently and release the brakes immediately after stopping then the car will leave the engine running. If, however, you leave your foot on the brake for a few seconds after coming to a stop, then the car will shut down the engine (assuming that it has sufficient power in the battery to do so).

So, if you want the car to shut off the engine whilst you are stopped, then you just need to to keep your foot on the brakes for a few seconds after coming to a stop, until the engine stops.

Hopefully this is helpful to someone.

 

[KXL]

Assuming Auto-hold is the thing that stops the car from rolling backwards on a slight incline? I never actually looked into this, sometimes I just assumed, huh, car doesn't want to go off (but didn't relate to where the brake pedal position is or conditions leading up to the stop). When that happens (and the AC is not on), then I would just double press the start/stop button, to 'force' the engine to shut off. Also if the steering angle is quite extreme when stopped, then the engine would not go off, no matter what I do.

However:
When I release the accelerator (say I can see a red light coming up), engine goes off, and if it's 15mph or slower before I press the brakes, the engine woudl stay off, until I press the accelerator again or release the brake.

In the same situation, but either the radar has picked up an object in front, and my closing speed is above 15mph or so towards an intersection (maybe it uses GPS?), the car would restart the engine (whether I press any pedals or not). Likewise when I'm approaching a 'raised' pedestrain crossing with the engine already off (coasting) it would re-start the engine just before it arrives there.

 

[AdamInKent]

Assuming Auto-hold is the thing that stops the car from rolling backwards on a slight incline?

Thanks for the additional info. There are two similar but slightly different hold functions in the car.

Hill Hold (I’m not sure if that is the right name) is a permanently enabled feature which holds the brakes on for a few seconds after they are released on an incline, to prevent roll back.

Auto Hold is optional (enabled from the MMI) and it keeps the brakes applied for an unlimited period of time until you touch the accelerator. It’s intended to hold the brakes on for you at traffic lights, in start-stop traffic or any other circumstances that you are stopped for a longer period of time. (It saves you the effort of keeping your foot on the brake or the need to apply the handbrake.)

 

[KXL]

Wait...so I pull up to traffic light with this 'hold' function on I can after I stopped, step off the brakes and the engine won't restart, and brake lights off until I touch the gas pedal? Normally I would pull up, put to neutral and release the brake. If it's on the incline I just engage the e brake. Ooh I learn something new everyday

 

[RichK]

Wait...so I pull up to traffic light with this 'hold' function on I can after I stopped, step off the brakes and the engine won't restart, and brake lights off until I touch the gas pedal? Normally I would pull up, put to neutral and release the brake. If it's on the incline I just engage the e brake. Ooh I learn something new everyday

Me thinks you should read your manual, there’s probably lots you will learn if you haven’t worked out these basics yet. Certainly no need for neutral in a modern car like this at traffic lights.

 

[AdamInKent]

Wait...so I pull up to traffic light with this 'hold' function on I can after I stopped, step off the brakes and the engine won't restart, and brake lights off until I touch the gas pedal? Normally I would pull up, put to neutral and release the brake. If it's on the incline I just engage the e brake. Ooh I learn something new everyday

Yes, with the auto hold function enabled (it is off by default) all you need to do once the car has come to a halt is to remove your foot from the brake pedal and the car will hold the brakes on for you (at whatever pressure that you applied) with the brake lights on. You can leave the gearbox in Drive (the car will handle the clutch).

The same brake-light in the dashboard which goes red when the handbrake is applied will show green when the car is holding the brakes in Auto Hold.

 

[KXL]

Certainly no need for neutral in a modern car like this at traffic lights.

Yup, though there is also a rule in highway code that states one shouldn't be holding the brake (with brake likes shining esp at night) at the red light. Hence why I put it to neutral, and the rear brake lights go off.

 

[AdamInKent]

Yup, though there is also a rule in highway code that states one shouldn't be holding the brake (with brake likes shining esp at night) at the red light. Hence why I put it to neutral, and the rear brake lights go off.

I definitely agree about not holding the brakes on if you have someone waiting behind you at night (eg at traffic lights). An alternative way of extinguishing the brake lights is by engaging the handbrake (with the car still in Drive).

Neutral is only really intended to be used if the car is being towed (or pushed), IIRC from the manual.

 

[RichK]

Yup, though there is also a rule in highway code that states one shouldn't be holding the brake (with brake likes shining esp at night) at the red light. Hence why I put it to neutral, and the rear brake lights go off.

It’s an automatic car (unless you choose paddles and manual), you put it in drive and drive.