the red light turns on when i push the button, but i wont heat up.. anyone know why??

 

more than likely the wires are broke because they're set too close under the cover. Common problem, but take it too a after market shop and you'll have a better heater than ever before.

 

There are many threads on this issue and is very common. If your car is still under warranty take it to your dealer. The heating element itself may have burnt out, the wires feeding the element may have burnt out or the control module may have also burnt out. The control module is part of the unit that houses the hazard lights switch and seat controls.

 

~ an expensive and labor consuming repair... been there twice luckily with the warranty.