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Seldom Used 2004 - Check Engine Light - What Next

Discussion in 'Gen 2 Prius Main Forum' started by baumgrenze, Sep 29, 2014.

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  1. exstudent

    exstudent Senior Member

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    Vehicle:
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    P1121 refers to the 3-way coolant control valve. Here was my experience with it. LINK.

    Here's a how to, if you want to change it yourself.
    P1121 - Coolant Control Valve Replacement (with pics) | PriusChat

    When did you buy this 2004? I ask cause the Hybrid Emission Warranty is 10Yr/150K miles, from date of purchase. I got mine replaced under this warranty on 1-28-2014, at 121,454 miles. The dealer probably wanted the warranty work, and pushed this through. I have heard of others not having the same luck.
     
    #21 exstudent, Oct 1, 2014
  2. baumgrenze

    baumgrenze Junior Member

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    It became ours on 5/20/14, so we are over 10 years by 4 months and change.

    Thanks for the links

    baumgrenze
     
    #22 baumgrenze, Oct 1, 2014
  3. baumgrenze

    baumgrenze Junior Member

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    I checked out the link:

    "Here's a how to, if you want to change it yourself."

    I checked our coolant level. It is not as trivial as in other cars I've owned. The radiator cap is hidden beneath a shroud that is held in place by 'Philips screws that are not screws' and the shroud warns of high voltage components beneath it. The level in ours was at the bottom of the filler riser. I topped it up. It took maybe a half-cup of water. The obvious reservoir is right at the 'full' mark. Is there any chance there could be air trapped elsewhere in the system?

    I was left 'unclear' about how critical this component is. My understanding is that it moves hot coolant to a Thermos like reservoir so that a bit less fuel is used to warm up the engine after, say, a 1-2 hour stop.

    We are contemplating a 600 trans-Sierra trip soon. Can I take care of it when we get back (if ever?)

    thanks,

    baumgrenze
     
    #23 baumgrenze, Oct 1, 2014
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Yes, it is possible that air is trapped elsewhere. How well does the cabin heater work, and do you hear air bubbling around when you have the heater on MAX HEAT and the cabin fan at high speed?

    If the cabin heater works well and you don't hear air bubbling in the heater core, then just check the fluid level in the radiator periodically. If you continue to need to add fluid, the correct fluid is Toyota Super Long Life Coolant.

    Also look at the engine coolant pump pulley for pinkish residue in the interior. If you see this then you should have the coolant pump replaced before your road trip.

    As to the coolant valve itself, you can ignore that indefinitely - except that will keep the check engine light on and you won't be aware of any other issues that may develop over time.

    Regarding the high voltage warning labels, those relate to the HID headlights so if you are not getting into the headlight assemblies while they are powered up, then no worries.
     
    #24 Patrick Wong, Oct 1, 2014
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