Question about 1992 Lexus Sc 400

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My heater does not work!! There seems to be a lot of temp. sensors and senders. What do I need to look out for? I think it may be a control switch or something along those lines. Is there a master temp control or something?

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If your AC is working with temperature control, then everything inside the cabin is OK. The problem is that there is no coolant flowing through the heater core. Either the heater core get clogged up or an electric valve control the amount coolant to the heater core gets stuck not opening when asking for heat. Have a shop check to see if there is flow or not when they do a flush on the heater core. Measuring the resistance is not telling the true story since the coil is never burnt, but the valve is stuck due to debris and residues from coolant flowing through. Hope it can help.

Posted on Nov 19, 2009

  • whoneedsthis Jan 26, 2011

    Had a similar problem -- all it was was the coolant was low.


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Are you me?

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