Check the heater core. There are two hose coming out of the fire wall that go to the heater core when car is hot check both hoses for flowing water. If you have flow both hoses will be hot if not 1 will be hot the other will be cold. ( clogged heater core ) the other and last thing to do would be to check the blend door motor witch is a big problem for gm cars. This motor sits on the door that will move air flow to the heater core or for the a/c (cold air ) this motor can be stuck or broken.That needs to be checked.
If the motor is not operating,then it has to be replaced.
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For more heater troubleshooting problems:---
Click the link below:---
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If the motor is not operating,then it has to be replaced.
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For more heater troubleshooting problems:---
Click the link below:---
heater not working on Lexus RX 300?
2000 kia sportage heater blows cold air?
No Hot Air from Heater and Defroster on Kia Optima...
Heater blows cold on dodge dakota?
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