Unable to reset to higher speed in DRCC

Why would it take more throttle changes holding 70 than 69?

 

I don't think it is holding 69. It's holding 69-70. Just like adjusting the thermostat on my house's air conditioner to a spread of 76-80 degrees rather than forcing to to keep cycling on and off to stay right at 79.

What I don't know is if ECO mode lets the speed drift more than Normal or Power modes.

 

In my experience it does. The kicker with drift is the level, it drifts high downhill, and low uphill, and low on flat. (but real rarely more than 1mph) My commute is mostly on DRCC. As a computer programmer, I believe it's just rounding and the speed really isn't changing that much. It'd be better if they added another digit.

 

I think we're talking about different phenomena. What I'm talking about is hitting the stick at 70 mph and letting up the gas and the car falls to 69 and stays there for a half hour or longer. Uphill, downhill, doesn't matter. It stays 69. When you give one bump up thinking it will move to 70, instead it moves to 71.

 

Above and below seem contradictory to me. In my experience it goes up and down by about 1 mph, usually on hills and not frequesntly, and it doesn't matter if it's DRCC, which I only use on long trips, or regular, which I use whenever I can on my commute.

I agree. That would be pretty cool.

 

Mine does that a bit, too. But it also sometimes goes up to 70 after a while.

 

I don't know why it didn't occur to me just to switch the display to km/h and see if the same thing happens. If it does, then it's probably as you and Elektroingenieur hypothesized. If it holds the set km/h then it's likely a rounding error issue.

 

I don't really see anything contradictory, it's all just a +-.5 with a real slight difference in speed. Some kind of fudge factor built in that it can drift by before it alters the throttle, it might even be by +-.5. It's true it more often reads 1mph lower, but that could be built into the fudge factor, say -.7 or +.3. Anyway, without that digit or some other way of getting the exact speed, only the people who programmed it can say.

I never use the standard cruise control, so i don't know how that works.

 

I think it's the same phenomena, though I see it change on slight hills, as that's all we have on my commute.

 

I do not know. I'd think the speed would have vary for it to be a case of minor speed variation.

EDIT - I type "I d u n n o" (without spaces) and the board software displays it as "I do not know" even though the source shows "I d u n n o." Strange.

 

As far as I know, it does vary.

 

That's why I think we're talking about different cases: I'm talking about when it doesn't vary, but it isn't the speed that was set.

 

Gotcha, more of an edge case compared to what I'm thinking.

 

I'm pretty sure we're seeing the same thing but it's hard to describe. The speed has to vary at least a little, but it seems to be little enough to very rarely make a change to the speedometer. And who know what the lag is for the speedometer? I'm sure it's very brief, but there's still a little delay.

That's an interesting test idea on changing to km, @PiPLosAngeles. I'd try it myself today, but I'm tracking mileage on this trip and, iirc, making that change resets the trip meter for the "since start" meter. I'm having fun tracking that, so I'll try it after we get home.

 

DRCC maxes out at 180 km/h

Who would ever use it that fast?!
More importantly, can there Prius even get to 180

 

It does 160 for sure. I didn't get the impression that another 20 kph would be a problem.