HyCam engine runs to make waste heat?

no, you just have a gray battery meter, unless they changed it in the latest generation.

prius has color: full = light green, middle = blue, low = purple not sure about gen 4 prius

 

in the Gen 2 Prius, if the top 1 or 2 bars were lit, the bars were green, the middle 6 were blue, and if it dropped to the last one or two bars, they turned pink/purple.

Newer Toyota Hybrids do not seem to have this feature, in part because you do not want the top two bars lit except for plug ins.
(if the battery 'fills' the car can't do more regenerative braking. You will see plug in owners complaining about the engine coming on going downhill; their battery has filled)
They became green more in winter, on my gen 2 as I ran the engine for heat, and incidentally charged the battery.

 

I think Gen 4 bars are all white. I remember my son's old Gen 2 having the colors.

EDIT: Poor memory. The bars are all blue in a white outline.

 

what do you mean, 'you think', don't you have a gen 4?

 

And apparently a poor memory. The bars are blue in a white outline.

 

yeah, i have to go out and look every time someone asks a question

 

I was driving home yesterday and realized my post was incorrect.

 

Toyota did a really braindead TPMS system. The car knows which tire is low, but the dashboard isn't laid out to present it to you, so the best it can do is narrow it down to the four that are on your car. At least you don't have to check the whole parking lot.

 

The base model "collected" heat from the exhaust manifolds.

 

you can read each tire with an old like scan gauge. otherwise, it is whackamole. but frequent pressure checks are better than waiting for lights.

 

It is just cold, all the tires are low. I put an additional 15 PSI in all 4 on Sunday.

It is really annoying when just one is low.

 

If it is like the Prius, the AC compressor is electric, so the engine only needs to run a little more to provide extra electricity. The Prime has a heat pump so it can provide heat solely on electricity too.

 

On our 2010 Prius, with a partially-warmed engine, sitting at a red light, I can quite reliably turn the engine off or on, just by ticking the cabin temperature up or down a degree or two. Putting the vent mode into heat/defog can do it too. The car's got logic, and if you request more heat it's more likely to fire up the engine.

 

Mazda's managed to set it up, so owners can initialize new sensors (say all season to snow swap) simply by turning the car on/off once, and driving above something like 25 kmh for about 10 minutes.

It might be dealership needs to do some initial introduction "hand shake", not sure.

 

IF......you really needed 15 PSI in all of your tires.......they were dangerously low to start with.
A drop of 40 degrees F will NOT cause that much change in pressure.