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A/C in Eco mode

Discussion in 'Gen 3 Prius Main Forum' started by malamalama, Jun 14, 2011.

  1. malamalama

    malamalama Junior Member

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    2010 Prius
    Model:
    IV
    Could someone please explain in detail what Eco mode does regarding the A/C? Everywhere I've searched and read, I find only general comments like "optimized for fuel economy" or "tuned to improve fuel economy" or "changes a/c operation". I'm looking for more details than that.

    Somewhere I've also read (in this forum) that it reduces max output. If that is the case, does that mean there is no difference between Eco and Normal mode a/c operation if the fan is set on low?

    I live in Hawaii, so my a/c is on all the time. I usually drive in Eco mode, but haven't found a difference in the a/c when switching to Normal mode.
     
  2. xs650

    xs650 Senior Member

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    If you set the AC to automatic and let it control the fan speed, the differences will be more obvious. On automatic mine often runs the fan slower in Eco and I also suspect but don't know for sure that it also doesn't run the compressor as hard in Eco.

    If I'm driving in Eco and it isn't clearing the windows fast enough in what passes for winter here or cooling down fast enough in hot weather, I switch to Normal until things are under control. It's like having an extra AC control:D
     
  3. tomlouie

    tomlouie Member

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    I totally recommend signing up at the Toyota website for the day pass to gain access to their Tech documents. Best money spent if you love technical details.

    I dug around my Toyota Tech docs and found this: "HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: SYSTEM DESCRIPTION (2010 Prius)". Here's the section about the ECO mode and AC performance:

    ==========
    9. ECO MODE CONTROL

    (a) Under the control of eco mode, the A/C amplifier restricts the air conditioning system performance under specified conditions, thus improving fuel economy.

    (b) Eco mode control is activated when the ECO MODE switch provided inside the integration control and panel sub-assembly is pressed, and then restricts the air conditioning system performance as described below.

    #1 Inside/outside Air Switch Control: Automatically switches the air inlet port to internal air circulation mode when the outside air temperature is equal to or higher than a predetermined temperature and reduces the power consumption.

    #2 Blower Level Control: Sets the blower level in AUTO mode lower than normal, and suppresses the power consumption. (

    #3 PTC Heater Control: Stops the operation of PTC heater assembly and suppresses the power consumption.

    #4 Heating Restriction Control: Changes the air outlet temperature by turning the ECO MODE switch on and off during heating and increases the amount of engine-off time when the ECO MODE switch is in the on state, thus improving fuel economy.

    #5 Compressor Speed Restriction Control: Restricts the maximum speed during cooling and reduces the power consumption.
    =============

    Personally, I don't like how laggy the gas pedal feels in ECO Mode, so I just leave the car in Normal mode.
     
    1 person likes this.
  4. malamalama

    malamalama Junior Member

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    2010 Prius
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    IV
    That's the type of info I was looking for. Mahalo!