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No Heating at All [11/2023 - ]: Description

If cool air blows from the registers regardless of the temperature setting of the air conditioning system, the following factors may be the cause.

Symptom Factor
  • No warm air comes out (Blower control is normal)
  • Outlet air temperature does not increase (Blower control is normal)
  • Engine coolant temperature (low)
  • Refrigerant volume (low)
  • Air mix damper and link operation (jamming)
  • Warm-up control
  • Blockage in heater radiator unit sub-assembly
  • Heater radiator unit sub-assembly malfunction
  • Flow shutting valve (water by-pass hose assembly) malfunction
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