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Check engine light related to super hot weather?

Discussion in 'Generation 1 Prius Discussion' started by ElizaDay, Sep 2, 2010.

  1. ElizaDay

    ElizaDay New Member

    Joined:
    Sep 5, 2008
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    Location:
    NORTHERN CALIFORNIA
    Vehicle:
    2001 Prius
    I have a super sensitive CEL light. It has lit up a few times in the past year.

    First time, the gas cap was loose
    Second time, I needed a new gas cap
    Third time, I let my gas get too low before I refilled it.

    Today it went on. It is insanely hot in Northern California. It was 104 degrees and I was driving with my A/C on but there wasn't much cool air coming out.

    Could the CEL be related to the hot weather?
     
    #1 ElizaDay, Sep 2, 2010
  2. freidawg

    freidawg Prius Recycler

    Joined:
    Aug 22, 2010
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    Vehicle:
    2003 Prius
    Model:
    N/A
    It could be and it could be an over heat issue.

    The car will store the codes in history and you can get at them with Techstream. If you know a place that would scan it without charging you an arm and a leg, it would be worth it to see what it was.

    Eric
     
    #2 freidawg, Sep 2, 2010
  3. 13Plug

    13Plug Active Member

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    Vehicle:
    2013 Prius Plug-in
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    If the light is coming on that often you might want to buy a CAN OBD-II code reader yourself. I have a ScanGauge II that I keep in the car, but I've only had my check engine light come on once. Was a p0031.

    And you should also bookmark OBD-II Trouble Codes - DTC Codes Car Repair if you're frequently getting trouble codes.
     
    #3 13Plug, Sep 3, 2010
  4. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Vehicle:
    2018 Tesla Model 3
    Model:
    Prime Plus


    Having a scanner would let you read the error codes as well as engine and other data. The prices range from $50 to as much as $1,500 with cost, quality and compatibility problems that need to be addressed. These units plug into a connector found at the bottom of the dashboard to the left the steering wheel:
    [​IMG]

    On Board Diagnostic (OBD) scanners have three major protocols of which our NHW11, 2001-03 Prius, uses:
    ISO-9141 - pins 7, 15 and for power, pins 4, 5 and 16
    KWP2000 - variable length packets
    ​
    The problem is most scanners test the other protocol and the more recent CANbus, pins 7 and 14. This test sends signals to Ts, pin 14, and induces false codes in the brake system. We can help you make what is called a 'pig-tail' adapter that keeps this from happening:
    [​IMG]
    Restarting the car without the scanner clears the false codes but this is not common knowledge.

    So let's go over the options:
    Column 1 Column 2 Column 3 Column 4 Column 5 Column 6 Column 7
    0 cost type characteristics
    1 $50-150 generic OBD May not support ISO-9141 may not read all codes limited engineering data because of auto-scanning they needs pig-tail adapter
    2 $10/mo $150 deposit Graham scanner I have two and rent them out selectable display values engine hybrid and battery ECU and codes
    3 $175 scangauge Supports ISO-9141 but needs pig-tail type adapter reads some codes but others require programming XGAUGE using Vincent's table
    4 $400 Auto Enguity requires laptop somewhat buggy it provides access to all controller and most vehicle data
    5 $1 200-1 500 Techstream Lite requires laptop a Toyota product it should be pretty much the same features as the shop scanner

    Bob Wilson
     
    #4 bwilson4web, Sep 3, 2010
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