Question about 1999 Chevrolet Silverado 1500

1 Answer

No heat , fan runs on speeds 3,4and 5 not on 1 or2

Heater hose in is warm heater hose out is cool, is there a fuse that controls the function?
is there a electronic operated valve to open and close the flow of glycol to the rad?
if so would there be a link why my speed control is not working on 1and2 .
I have 330,000 kms I should expect some problems right!

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  • 1 more comment 
  • herb_grasser Dec 09, 2008

    Dropped unit off at Canadian Tire as I'm in the middle of a city,

    I mentioned the fix and I hope it works ....Thanks this link is a great idea!!!

  • tdrake83 Dec 12, 2008

    My heater blows cold air. Would this also be contributed to a blockage in the hoses. Where exactly is the heater core located?

  • Anonymous Dec 22, 2008

    heater works but the blower only works in 4 and 5 sp

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  • Master
  • 1,450 Answers

Coolant flows thru heater core all the time temp is controlled by doors.you have a blockage in core,try removing hoses and backflushing heater core probably a little bit of scale stopping inlet.the fan speed is probably the blower resistor it is locateed next to blower motor under dash check the plug they burn up

Posted on Dec 09, 2008

  • TripleTauto
    TripleTauto Dec 09, 2008

    let me know if it does and if so please rate as fixya

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heater_core.jpg
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