Temp idiot light

Discussion in 'Technical' started by 67fstbk, Jun 3, 2016.

  1. 67fstbk

    67fstbk Member

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    Can anyone tell me if the temperature light should come on when you turn the ignition on? Right now I have an oil pressure in an alternator light and that is it . I was under the impression that all lights should come on when ignition is turned on without the car running. I have had lots of issues with the printed circuit behind the instrument cluster and I'm worried that I'm going to have to pull that whole thing out again to make sure that this light is functional. I'm afraid I do not have a temperature sensor at the moment and definitely do not want to go mechanical. Actually, I've never really understood how electronic sending units work. Do they close a circuit when there is a fault?
     

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  2. Krazy Comet

    Krazy Comet Tom

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    AFAIK the only time temp light comes on is in a overheat condition... To test, ground the wire on temp sensor(red/wh stripe), if light comes on circuit is good...
     
  3. 67fstbk

    67fstbk Member

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    Thanks! I actually thought of this and tried it shortly after making the post....it works!
     
  4. Krazy Comet

    Krazy Comet Tom

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    LOL I tested mine and it doesn't come on, but I have a set of gauges so don't really care...
     
  5. Crazy Larry

    Crazy Larry Member

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    The Temp light should come on during cranking, but not just with the key in the "on" position.
    Oil & Alt should come on with key in the "on" position.
     

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