Cruise control on the cheap!

[Mike J.]

4 minutes ago, Mick F said:

Tried it. Not true.  I experimented as a result of another thread on here.  The car increases speed even thought he battery isn't full.

Read the handbook.

 

Reread my post. To help in this matter:

"the regenerated energy is lower than the maximum allowed".

I cannot accept your statement of "not true" until you publish your 'experimental' figures for the regeneration values through Hybrid Assistant or similar. It shows a recovery by coasting graph. The maximum I have seen is around 17kW, but my hills are 'short'. You have to prove that speed increases when the regeneration is lower than the maximum allowed before your 'not true' statement is true.

[Mick F]

OK.  I'll bite.

There's another thread on here started by me about brake lights on a Yaris Hybrid.  I asked if the brakes came on in gear selected B.  They do not.  Then the subject went onto brake lights in cruise control going down a hill.

I made the point that the our hybrid increases speed coming down our local hill 30 limit A390 into Gunnislake Cornwall.  It was suggested that I tried it again with the Battery not fully charged.  I made it there only a week or so ago with a half-charged Battery, and I've done the same only a couple of days ago.

The cruise control really tries.  It really does, but engine braking on recharge isn't nearly enough to hold back down to 30mph going down a 15% hill.  I couldn't safely (or legally) get round the top LH corner without hitting the brakes.

As for Hybrid Assistant, I need an Android phone and a bluetooth OBD unit.  Neither of which I have or want.

Have a look the map to see where we are.  Gunny Hill is a pig and about a mile long though only half a mile on the steep bit.  Cruise control does not work to hold a hybrid car back at 30mph coming down.

Best wishes, Mick.

[Mike J.]

31 minutes ago, Mick F said:

OK.  I'll bite.

If you notice, my extra comment, "the regenerated energy is lower than the maximum allowed", was added to acknowledge your useful info from the original thread, but you just post that I was wrong. Your experience does not invalidate my 'extra' comment. We basically need more info that the App would supply.

[Mick F]

I understand that you might like more info, and TBH the technician in me would like more info too, but the plain and simple fact is, that CC does not hold my Yaris Hybrid at 30mph coming down Gunnislake Hill at all.  Absolutely not.

I've experimented quite a bit with CC over the past few weeks, and at normal speeds on normal roads, the speed is correctly and thoroughly adhered to.  The A30 west of Exeter is a case in point.  Some rather steep hills for a dual carriageway, and I can go up and down them solidly at 60mph.  In fact I was very impressed!  Some of those hills mean business.

I wonder if the speed is the thing here?  Gunnislake Hill A390 is a 30 limit ............ though you wouldn't guess it by the way some folk speed up and down there .............. and I wonder if it were a 50 limit, that the car would manage to hold it ok.  30mph in a normal car needs brakes most of the way down as 3rd gear won't be enough.  Automatics have a terrible time hanging on to the footbrake, but at least we hybrid drivers can select B and use the engine to hold us back that works well instead of using the brakes alone.

I wonder if in CC trying to hold it at 30, I could try selecting B?  Would that disengage the CC like braking would do?

Sounds like another experiment  ...................... but it will have to wait as we're away for a week as of tomorrow morning.

Mick.

[YarisHybrid2016]

Simple question: when the CC is engaged, does the needle go into the blue (CHG) zone at all? On mine it goes all the way to the bottom if necessary. If that is inadequate, then the car will accelerate, but it will also be at max regen doing so, and requires intervention with the foot brake to hold the speed.

If the speed downhill can be held at max regen or less, then it holds the speed without issue.

[Mick F]

I'll check how far it goes into the blue zone, but yes it does.  It'll be a week before we come back down the hill to check.

Mick.

[Mike J.]

On 11/16/2017 at 5:42 PM, Mick F said:

I wonder if in CC trying to hold it at 30, I could try selecting B?  Would that disengage the CC like braking would do?

I have used the B mode for the first time and confirm that CC is disengaged and remains disabled even when not slowing.

[pshawfocus]

Neither of my two previous Prius (NHW 11 and NHW 20) would hold the car at a speed when descending a hill whilst using cruise control.  I have no reason to believe Toyota have specifically engineered that into the new Yaris Hybrid (mine should arrive late Dec).

Regarding CC on the cheap, the NHW11 Prius that I owned had the option of CC which wasn't fitted to my car.  I sourced a replacement steering wheel with the CC levers from Toyota in the US, took the car to Yeoman in Brighton who they took the old wheel off, fitted the new one and hey presto, 60 mins later I had a Prius with CC.  I'd have every suspicion that it's possible to do much the same thing with any Toyota Hybrid as the functionality is already inbuilt, it just needs the appropriate CC levers plugged in.  

As I'd love at some point to get myself another NHW11 Prius I have also got what must be one of the last few remaining CC equipped spare steering wheels still in a Toyota box in my garage (I ordered another about 7 years ago after selling the NHW11 and then regretting it :-(  )  

[Mick F]

On 17/11/2017 at 12:09 AM, Mick F said:

I'll check how far it goes into the blue zone, but yes it does.  It'll be a week before we come back down the hill to check.

Mick.

Checked yesterday evening. The dial goes about half way into the Blue.  It goes fully to the bottom when I brake, but will not hold back to 30mph down the hill.  I didn't (forgot?) to check in B mode.  Seems like it wouldn't allow CC in B anyway.

Mick.

[FROSTYBALLS]

On 22/11/2017 at 7:41 AM, pshawfocus said:

....... new Yaris Hybrid (mine should arrive late Dec).

So if it is first registered in December 2017, please edit the 'Toyota Year' on your profile to reflect that legally it is a 2017 car.

[pshawfocus]

You don't believe in time travel?

[Mick F]

This is very much off-topic, but Next Year's products come out late This Year.  No doubt this is the same with cars.

Mick.

[Mike J.]

On ‎25‎/‎11‎/‎2017 at 12:42 PM, Mick F said:

Checked yesterday evening. The dial goes about half way into the Blue.

I have managed to check the operation in my car. Cruise set to 30mph and descending a hill at 40mph. Foot off accelerator and CC tried to lower speed to 30mph - it got there in the end, but the regen only went to the second mark (CHG area) and not to the maximum (3rd mark) which can only be reached using the brakes.

Suddenly thought that our cars have 2 regen levels (some EVs have changeable regen) - normal and high. High occurs when you have set a low mph via CC and are doing 10 -20 mph above it - foot off accelerator then gives high regen (retardation).

[YarisHybrid2016]

On 11/22/2017 at 7:41 AM, pshawfocus said:

Neither of my two previous Prius (NHW 11 and NHW 20) would hold the car at a speed when descending a hill whilst using cruise control.  I have no reason to believe Toyota have specifically engineered that into the new Yaris Hybrid (mine should arrive late Dec).  

Cruise definitely can use regen braking to hold speed down hill. Obviously if the hill is steeper than max regen can control the speed, the car will accelerate, but you get the idea. :)

@Mike J.: Interesting observation. Wrong time of year for it now, but there is a hill I can try this on. 30 MPH is sporting in dry weather (lots of corners), so I'm not trying it at the moment!

[pshawfocus]

I think we're probably all on the same page, I think it's a terminology thing.  I don't consider my car (my CT200h) to be 'braking' when I release my foot from the gas pedal.  I simply consider that Toyota have engineered regenerative drag into the system which is many ways mimics the engine braking you get from a conventionally equipped ICE.  If I brake to prevent the car from speeding up as it descends a hill, then that's regen braking, but if the car is descending a steep hill on CC, then the car will not 'brake' to hold it's speed, it will simply release the gas, but if the hill is steep enough, the car's speed will still increase as the forces of descent overcome the 'drag'. 

[Mike J.]

1 hour ago, pshawfocus said:

I think we're probably all on the same page, I think it's a terminology thing. 

Nope, there are definitely 2 levels of regen in my Yaris, the normal and the CC enhanced. You only have to look at the CHG display to see the difference if you don't notice the physical effect.

[pshawfocus]

As I'm still waiting for mine to pop out of the factory I'll have to defer to your greater knowledge.  Maybe Toyota have tweaked the CC / regen on the Yaris vs the other Toyota hybrids I've had.  Something new to try out  :-)  

[YarisHybrid2016]

11 hours ago, pshawfocus said:

but if the car is descending a steep hill on CC, then the car will not 'brake' to hold it's speed, it will simply release the gas 

Interesting. What model year was it? The Yaris definitely "brakes" (goes much further than simply idle throttle) to hold speed down a hill.

The first time I encountered it, it was a little disconcerting!   I've got used to it now (it feels weird as it actively retards the speed unlike in manual driving where you just lift off).

[pshawfocus]

12 hours ago, YarisHybrid2016 said:

What model year was it?

Both my previous Prius (2001 and 2008) 'did this', however, perhaps this is where my argument unwinds because neither had a charge meter the same as the Yaris so maybe....they were also doing it even though I never felt it or could see it from the monitors.  I will happily correct myself when my new Yaris arrives and I've been out to play in it  :-)   

[Mick F]

14 hours ago, YarisHybrid2016 said:

The Yaris definitely "brakes" (goes much further than simply idle throttle) to hold speed down a hill.

The first time I encountered it, it was a little disconcerting!   I've got used to it now (it feels weird as it actively retards the speed unlike in manual driving where you just lift off).

Yes, ours does that, but only on gentle hills.  Anything steeper, and the retardation isn't nearly enough unless it's a high enough speed perhaps.  Yet to try a steep hill in a 50mph limit for instance.

I think I'm correct in saying, that the "braking" is provided by regen plus the engine being turned without fuel input.  ie not actually running, but being turned.

Mick.

[Mike J.]

1 hour ago, Mick F said:

I think I'm correct in saying, that the "braking" is provided by regen plus the engine being turned without fuel input.  ie not actually running, but being turned.

Nope. That only occurs in B mode and CC is disabled in B mode.

[Mike J.]

1 hour ago, Mick F said:

Yes, ours does that, but only on gentle hills.  

Nope, it is not dependant on the type of hill. It is dependant on the regen limit and the speed differentials. The regen limit under CC is shown on the CHG display and mine hits the second position as the max.

[Mick F]

OK, I'm wrong about how it works! 

CC will not hold on a steep long hill at 30mph no matter how it works and no matter how much or little the Battery charge.  It honestly will not.

This hill is local to us, and we're up and down it most times we go out.  I know it intimately.

A390 travelling from the east from St Ann's Chapel, the hill gets steep just before the lefthander just before the entrance to the station.  It's a 30limit from before St Ann's Chapel and all the way into Gunnislake village.  The car is happy in CC at 30mph right through St Anne's but as soon as you hit the steep bit, it runs away as it will not hold back enough.  By the time you hit the bend, you have to brake to get round it when doing (illegally) 38mph.

Mick.

[Mike J.]

16 minutes ago, Mick F said:

OK, I'm wrong about how it works! 

CC will not hold on a steep long hill at 30mph no matter how it works and no matter how much or little the battery charge.  It honestly will not.

We need to know the CHG settings when the speed fails to hold the speed - my guess is you have reached the second marking which seems to be the max regen level.

[Mick F]

Yep, I reckon you're right. Once it reaches the max regen level, that's it.  The CHG will go right to the bottom under braking, but not under CC retardation.

The handbook says CC won't work on a steep hill ................. but it doesn't say why.

Mick.