Rev ICE, MFD, & Checking RPM

Not sure exactly what you're describing WRT the drive-in situation. Did the ICE light spontaneously? If so, it's almost certainly because your battery dropped below a certain level (were you running AC?). The car is very protective of the battery and won't let its charge drop below a certain level.

Revving doesn't stop the charge. If anything, it increases the current flow. Folks do it intentionally in certain circumstances (e.g., for experiments or before an MPG competition) to top off the battery (8 green bars). It's called "force charging." After that, the ICE will back down on its own regardless of how much you've got it floored. The car also protects it from overcharging.

I'm not sure why the MFD would show a cessation of current flow into the battery. Maybe it was topped out by then. But then if the battery was full, I wouldn't think you'd see a resumption after lifting the pedal. I've done force-charging a few times, but always monitoring CAN-View, which preempts the stock MFD display. I can tell you that CAN-View always shows significant current flow into the battery during a force charge.

This all assumes you're in D. If you're in N, nothing happens when you hit the go-pedal.

No way to monitor ICE speed without added instrumentation. ScanGauge is among the more popular devices, but a simple analog tach from Pep Boys will do the trick too if you know how to wire it up.

 

To clarify, the rev-up while in Park *does* stop the charge.
It's a different defined functionality, which takes over while
there's input from the user. There seem to be two stages of
rev-up or what Toyota calls "racing operation", 1500 rpm and
2400 rpm. Once you let go of the pedal the system can go back
to whatever it was doing before, charging if it needs it or
just sitting there with the engine off.
.
Go-pedal pressure in Drive with the brake held is force-charging,
a totally different scenario. It most likely exists because
auto techs use similar techniques to load-test engines against
automatic transmissions. In that case the only output is heat
buildup in the torque converter, so you probably don't want to
do it for too long. In our case the energy's got to go somewhere
and what better place than the battery? But you can't stuff
charge into there indefinitely, so once again the available time
for such a test is limited.
.
_H*

 

Hmm, hadn't thought about the P scenario. But then, I wouldn't have known how it behaves there anyway. Thanks yet again for a Prius tech tidbit.

 

I'm not sure how anyone can get the ICE to rev. when in "D". Pearl only revs. up in "P". In "D" she just pushes harder against the brakes, but doesn't rev the ICE. Trust me, in winter, sitting in a very cold car in warmup, it would be nice to rev. the ICE to make it warm up faster. I found last winter the only way to do so was in "P". Part of why my friends tell people the Prius has a "gas heater".

 

Hi David,

When the Prius is READY and in D, press on the brake pedal with your left foot to hold the car stationary. Floor the accelerator pedal with your right foot and hold it floored.

 

Which does nothing but press against the brakes a little harder. The ICE does not rev up. Perhaps I'm not waiting long enough, but I did try for a few seconds. So I shift to "P" and rev it to get a faster warmup. All while waiting at red lights, and only for the first 5 min or so of operation (car will not warm up while idling - it actually cools off when ambient temps are below -15C or so).

 

In D it doesn't really rev higher, it *loads harder*. More
current to the battery, wider throttle opening. Listen
carefully, you can probably tell it's happening.
.
Don't let go of the brake pedal when you're doing that...
.
_H*

 

The engine DOES come on in D if you floor it.