1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Outside temperature Prius 2008

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by denmac7, Mar 28, 2012.

  1. denmac7

    denmac7 New Member

    Joined:
    Mar 27, 2012
    10
    0
    0
    Location:
    West Virginia
    Vehicle:
    2008 Prius
    Model:
    N/A
    The outside teperature doe not show on my display.
    How do I fix it?
    Dennis
     
  2. KK6PD

    KK6PD _ . _ . / _ _ . _

    Joined:
    Mar 24, 2008
    4,003
    944
    118
    Location:
    Los Angeles Foothills
    Vehicle:
    Other Hybrid
    Model:
    N/A
    You could replace the sensor, they do go bad. You could reseat all the connectors on the MFD, it might just be a loose connection!
    Do you see anything in the location where the display normally is, like a -- or __?
    I am not sure where the temp probe resides on a 08. I will have to look through the Service Pdf's I have.
    Anybody else know offhand?
    Good question.
     
  3. denmac7

    denmac7 New Member

    Joined:
    Mar 27, 2012
    10
    0
    0
    Location:
    West Virginia
    Vehicle:
    2008 Prius
    Model:
    N/A

    The display shows "--" where the temp should be.
    Where are the connectors located.
    I have a 2008 repair manual but find no mention of the outside temp sensor.
    Also, the dispay will suddenly display the red triangle , check engine, VSC and another symbol while simultaneously disengaging the cruise control., The VSC and other symbol eventually disappear and the cruise control resumes working. Eventually the red triangle and check engine lits also disappear.
    The local Toyota dealership has found no problems listed in the computer history and I guess if there was such a problem, it would not spontaneously correct itself.
    I replaced the 12V battery two days ago to no avail.
    Incidently, I purchased this vehilcle used a few weeks ago. It only had less than 19,000 miles.
    Thanks for the response.
    Dennis
     
  4. jdcollins5

    jdcollins5 Senior Member

    Joined:
    Aug 30, 2009
    5,131
    1,338
    0
    Location:
    Wilmington, NC
    Vehicle:
    2010 Prius
    Model:
    III
    The 2010 outside temperature sensor is located in front of radiator just behind the front grill. I would guess that yours would be in the same general location. There should be a connector at the sensor for testing.

    It sounds like you may have greater issues than just the temp sensor not working though.
     
  5. KK6PD

    KK6PD _ . _ . / _ _ . _

    Joined:
    Mar 24, 2008
    4,003
    944
    118
    Location:
    Los Angeles Foothills
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Yes I have to agree with jdcollins5 on that! If you have a camera you can keep with you, or in the glove box, take a pic of the warning lights. That might be helpful next time you show up at the dealers. I do not think a bad outside temp probe would throw all those warning lights! However, with the car computer, outside air temp may be involved in the proper running of the ICE! Checking the battery was a smart move, that is eliminated!
    Just be sure to take pics safely if you are moving. I have done it, but it is a distraction!
    Keep us updated, this is an interesting problem, hopefully you resolve it quickly!
     
  6. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    337
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    The service manual that I have says that if the ambient air temp sensor is open, then the temp reading will be -40C. If it is shorted, then the temp will show 140C. I don't know if this has changed in subsequent years.

    The ambient temp signal goes to the engine ECM, which then passes this over the CAN bus to the Gateway ECU, then via the BEAN bus to the air conditioning ECU and via the AVC-LAN bus to the MFD. Which goes to say that it snakes through a *lot* of wiring.

    I might try and find the thermistor and both open and short the wires, and see what happens on the display. If you can measure the voltage on the thermistor, it should be around a 1-2 volts. Since the data goes out on the CAN bus, it should be possible to read this info with a CANbus interface and software, like Priidash.

    Does the A/C or heater temp control work? If the ambient sensor is not OK then the controller won't know when to shut on/off.
     
  7. denmac7

    denmac7 New Member

    Joined:
    Mar 27, 2012
    10
    0
    0
    Location:
    West Virginia
    Vehicle:
    2008 Prius
    Model:
    N/A
    The A/C and heater temp are displayed.
    What does the sensor look like? I have not been able to locate it.

    When I installed a new 12V battery, I noticed that the terminal section of air duct from the battery is missing. How significant is this RE: the performance of the vehicle?
    Thanks,
    Dennis
     
  8. nh7o

    nh7o Off grid since 1980

    Joined:
    Dec 10, 2011
    1,686
    337
    0
    Location:
    Hawaii
    Vehicle:
    2009 Prius
    Model:
    II
    The A/C and heat temps would be settings, rather than measurements. I think only the outside ambient temp is an actual measurement.

    Here is what the service manual says:
    The sensor is a little blob plugged into a two pin connector. I would definitely try to use some CAN bus scanner to see if the data is being generated properly.
     
    1 person likes this.