New Hybrid Owner

[Unholy Muppet]

Hi fellow Auris owners.  I've had my 63 plate excel hybrid for around a week now and I'm really liking the smooth ride and comfort but could someone clarify for me that the rumble/low grinding noise when the car is in B mode and coasting is normal?  It's like a subtle vibration.  I can feel it slightly through the car more at speeds below 30.  I'm not overly familiar with these so unsure if it's normal.

A little info about the car.  It is a 63 plate, bought from a Toyota dealership and has only covered 25000 miles.

I'm just trying to learn about it's traits as this is my first foray into hybrid driving.

Cheers guys and gals.

Paul

[Bob110023]

Hi unholy muppet and welcome. I use my B mode when going down a hill, this recharges the Battery. There is a very slight vibration but I think this caused by the torque generated while recharging is taking place. You can feel it as it is like a braking system. I have a 2016 business edition on a 65 plate. Love it. Happy motoring. 

[Unholy Muppet]

Hi Bob and thanks for the reply.  Can i ask, is it noisy when coasting in B?  It sounds to me like it's grinding slightly.  Again, that may be totally normal.  Like I say, I'm unfamiliar with the vehicle at the moment.

[Bob110023]

Hi Paul. No it is not noisy. I can only just feel the torque prodused through recharge. Perhaps you should visit the dealership and go out on test with a technician. 

[Catlover]

Hi Paul, I bought a 201 Auris Hyb 12 months ago, then bought myself a 2010 Prius and gave the Auris Hyb to the wife.  I hardly had the opportunity to use B mode, only when I went to the Derbyshire peak district and needed it then coming back down a steep hill into Macclesfield.  To be honest, I didn't feel any vibration that took my notice.  I notice you are in Cambrideshire, which I thought was fairly flat(ush). What circumstances are you using B mode???

[Unholy Muppet]

Hi Catlover.  I use it on slip roads, coasting up to junctions, things of that nature. Because the speed limits around here are so low I like to keep the Battery as topped up as I can. I don’t ever drive with it in B mode, only coasting. 

[Catlover]

Glad to hear that you don't drive your hybrid in B mode, Paul. That would be very detrimental to at least your fuel economy.  B mode is a braking mode, primarily to help when going down hills. In a "normal" car ie petrol or diesel, when going down steepish hill with foot off throttle the engine will still be running and give you some braking effect (that is as well as using the car brakes). With a hybrid, when you take your foot off the throttle, as when going down a steepish hill, its the engine will mostly cut-off, therefore you are relying on the cars brakes only. Consequently Toyota give us a B mode (B for braking assist) which is used only for going down steepish hills to give some braking effect because your engine cannot. Once the hill is finished you move the car out of B mode.  The tip someone gave on this forum was when you have a slippy surface ie snow, and you driving carefuly to avoid wheel spin, engaging B mode may help stabilize the car.  

When I was buying my Auris Hyb, the sales person (it was not a Toyota dealership) didn't know what B was for. Many have thought it has something to do with a "boost" for the engine, or B for a help with the Battery.  B is for braking, so if you use it, say, to coast, then you are actually slowing the car down thus not coasting as far as you would without B engaged.  As for wanting to keep your hybrid Battery topped up, as soon as you take your foot off the throttle then you are putting a charge into your Hybrid Battery. Just driving along normally using the petrol engine you can see this effect in one of the Displays available from your steering wheel. In diagrammatic form you get a display showing wheels, engine and Hyb battery.  As you drive this will show the various scenarios that the Hybrid system goes through, whether its the petrol engine driving the wheels, or the Hyb battery driving the wheels via the motors, or the wheels operating the hybrid motor to charge the batteries. Its interesting to watch - but be careful to keep your eye on the road!

[Bob110023]

Very well explained Joe.

[myriagon]

I very rarely use B mode - only on very steep downhills and we don't have many of those in Herts.

Using B mode in normal driving conditions uses more fuel - see http://blog.toyota.co.uk/hybrid-driving-technique-toyotas-top-tips-for-achieving-the-best-fuel-economy-in-your-hybrid