Car heater blowing cold air when turn on full speed

Hi I just bought a 2003 TOYOTA YARIS GS 998CC. My problem is this when I turn heater to the warmerst setting and then put on high I only getting cold air but if I have it set on lower speed I get luk warm air. I have plenty of cooliant and both hoses are heating up with no signs of leeks. Can anyone help explain what might be wrong

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JP993 profile image89

JP993 says

5 years ago
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Hawkesdream says

4 years ago
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nifty@50 says

5 years ago
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