Energy Monitor

[RolandB]

We now have about 3,000 miles on our Hybrid and I have spent much time (probably too much) viewing the Energy Monitor screen with the intent of understanding what is happening with the MGs and the Engine! Unfortunately, it is hot in Dallas this time of year and I keep the A/C on all the time. As I have seen, it is an electric compressor and thus is a drain on the battery system. I don't know if this is a contributor of the small amount of life the battery has before the engine kicks in. Most often, the Energy Monitor is pretty logical but then I've started wondering about why the 'yellow' arrow from the MG to the battery! I have accepted the 'green' arrows to the battery to demonstrate that the battery is being charged from the MGs (front and/or rear). I have noticed the two-way 'yellow' flows and when the MG has the 'yellow' arrow from the battery, I have assumed this meant the MG was getting power from the battery to drive the front wheels (haven't ever seen the 'yellow' arrow from the rear MG). Most often, when I see the 'yellow' arrow going to the battery, I also have a yellow arrow from the engine to the MG and a 'yellow' flow to the front wheels. Anyone know what the colors are for? I understand the three colors used for the battery with the three (very well, regular, very low) charge status. On another issue, I have been stopped at an intersection (with foot solidly on the brake) and seen both the engine and MG supplying power to the front wheels (the wheels on the display are stopped however)! Usually, when stopped, I don't have any arrows to the front wheels even though the engine may be driving the MG to charge the battery. Any comments?

[wwest]

On the 2nd gen Prius there is a c-best option wherein the climate control reheat/remix mode is disabled.

If the RX400h doesn't have this option then you can accomplish the same thing by putting the system in max cooling and recirculate and then using the blower speed to regulate the cabin temperature to your comfort level.

DO NOT USE RECIRCULATE DURING COLD CLIMATE CONDITIONS.

The only downside is that the system airflow will be so cool it will be a bit discomforting until the cabin has cooled to your comfort level and the blower speed can then be significantly reduced.

The upside(s) are that the A/C system will be a LOT more efficient resulting in the A/C compressor not running nearly as often. The second advantage is that in order for the remix/reheat cycle to be used the ICE must be run fairly often to keep the engine coolant temperature up to a satisfactory reheat level.

With no system airflow being reheated the coolant will stay hot longer and then the only reason for the ICE to run inordinately (other than for motive force) will be to keep the catalyst HOT.

Yet a third thing you can do is install a manual shut-off valve in the engine coolant heater line within the engine compartment. Closing the valve during the summer months will result in a much higher level of A/C efficiency overall.

Also, you can then run the system in fully automatic mode with no concern of the level of reheat commanded by the system. This will also prevent the system airflow from even being heated from radiant effects within the A/C plenum.

[jj_fender]

I have had my RX400h since April and have noticed something very peculiar about the Conservation Monitor on the NAV Display.

Like another post, I have spent entirely too much time looking at this thing.

Normally when the display shows only green arrows (charging the battery) the MPG says 99.9...but when the car is parked for a few hours this is not the case. Let me explain...

I park in a parking structure on the forth floor. When I start the car after work I cruize all down hill through the parking garage...nothing but green arrows pointing toward the battery symbol or the battery running the electric motors. Either way the MPG shows 6.7, 8.2, 12.0, 11.3 ... etc... all the way down the parking garage. When I get to the bottom and cruize a bit, it goes back to the 99.9 display when coasting or using the electrics.

How can this be? Has anyone else seen this phenomenon? I would think that it would immediately display 99.9 MPG when not using the ICE.