I think ECO mode does have an effect in the summer too, with some effect on the way that the A/C compressor runs.

Try doing what you did before and see if pressing the "Off" button on the climate controls allows the ICE to shut off.

 

I have found that eco mode so far only controls the fan speed....I'll have to try it off to see if it heats right away as it should with an electric air heater - but I doubt they use one as they require a lot of amps and could be dangerous....

Another note to remember is if you have it in Auto mode - the fans will not turn on until the engine is warm.. We have had several below 30d nights and days here in Colorado and I have found in the cold car - it takes a good mile or two before the fans kick in on Auto Mode....

 

I don't think it has an electric heater - off eco mode - it still doesn't kick on for a couple minutes in the cold mornings....just turns the fan on higher...

 

The TCH does have an electric heater for heating passenger compartment air. It uses electricity from the 12-volt battery, and operates only when ECO mode is "off." If ECO mode is "on," the heater fan won't turn on until the engine coolant reaches above 45 degrees Celsius (113 degrees Fahrenheit). It is then necessary to keep restarting the ICE when the outside temperature is low, in order to maintain the coolant temperature for heating purposes. [ECO mode "on" also reduces A/C power drain on the NiMH battery (the A/C runs off the high-voltage battery) in hot weather.] By the way, the temperature gauge in the instrument cluster reaches the displayed "operating temperature" indication (1 division below half-way on my TCH) at 60 degrees Celsius (140 degrees Fahrenheit), and stays there as the coolant temperature continues to rise further. I've not seen the pointer rise above this point thus far. Hence, it is a poor indicator of the actual ICE temperature above 60 degrees Celsius. My guess is that Toyota have probably done this so that the user doesn't see the ICE temperature continually going up and down, as it cycles on and off, especially in cold weather. But it is going up and down. You'll only see this on the display, however, if the temperature drops below 60 degrees Celsius.

Stan

 

I was sitting at a stop light (with the heater in ECO mode), and the ICE was stopped. As I waited for the light, I was watching the temperature gauge drop as the heater seemed to extract heat from the coolant and warm the cabin. It actually dropped one "tick" level on the gauge before the light turned green.

When you say that the guage won't climb any higher, is there an exception when the engine overheats?? Will it indicate this, or is there an idiot light for this purpose?

 

Cool info Stan, where did you find this out? My TCH is in the garage overnight so no frosty windows yet, but are you saying that the TCH will be able to put out warm(er) air almost immediately to defrost windows?

Also, about the temp guage. Yea, I've noticed that the temp guage does not vary nearly as much as one might expect. Again, where did you come up with this tidbit? Doesn't seem to make much sense to put an analog temp guage in a car and then use it as an indicator light. I had assumed it didn't vary much as the TCH had a decent thermostat and some kind of better insulated cooling system rather than a misleading guage. Just an assumption though, I don't have any ***** left to start a new tennis match with you and this thread

 

spiff72 — Clearly, if the coolant temperature gets too hot, the gauge will start rising above this "-1 tick mark below center" position. What I meant is that, in my driving so far, I've not seen it do so, and so I can't say at what coolant temperature it will start rising again.


Droid13 — I found out the information about the electric heater by perusing the circuit diagrams in the Camry Hybrid Repair Manuals. The information about the water temperature I found out by using my ScanGaugeII — look in my post on thread "An Unpalatable Fact (with apologies to Al Gore!)" for more information on ScanGaugeII. I have it reading ICE water temperature (as one of the four selectable sensor readings that it can display simultaneously), and so I can see its correspondence with the water temperature gauge's reading. [The other three sensor outputs that I currently monitor are: ICE rpm, ICE % load factor at that rpm, and instantaneous fuel economy in mpg (which goes beyond 60 mpg).] ScanGaugeII can be switched between US and metric units, and it has taught me a lot in the month I've had it. I would certainly recommend it to technically interested owners — but unfortunately (at least, in its current incarnation) it doesn't display any hybrid-specific sensor outputs.

Stan

 

Found something interesting this evening. I had the climate system in AUTO mode. I was almost home and decided to turn up the temp 1 degree. Looking down I noticed that the ECO display was not illuminated so I pressed the switch. The TCH had been blowing air out of both the foot vents and the dash vents. When I turned on ECO mode the dash vents turned off. I turned it on and off several times, both then and the next time I was in the car. The results were always the same. ECO on - only floor vents. ECO off - both floor and dash vents.