My 2002 silverado heat wont shut off

check heat hoses going into fire wall to heater core should be hot when engine warm solution clogged hoses going to heater core

the heat is independant from your ac. look for leaky radiator hoses or heater hoses,radiator cap,coolant

leaks inside your cab under the dashboard on your floor board. if you have non of these problems.

you may have a blocked or stopped up heater core and it will need to be replaced. depending on the

truck some replacements are easy and some hard , trucks and cars vary. good luck!

Check the coolant level first. Low coolant usually affects the heater first. Check you temp gauge and make sure its getting up to temp. Carefully feel both heater hoses where they go thru the fire wall. They should both be about the same. If one is noticably cooler than the other you have a restricton in the heater core and will need to replace it. On some air condition models there is a vacuum operated shut of valve to the heater when the a/c is in use. Your temp selector could be bad in the das or you could have a vacuum operated "shunt door that is not working.
These are pretty much listed in the corrrect order.
Lee

the windings in the coil on the compressor clutch is shorted,you need to remove the drive pulley where the belts hook on the compressor,then unbolt the 4 bolts holding the coil assy

that fuse powers pcm fuel heater and some other things. when the fuse blows the pcm shuts down. causing it to not run. usually its the heater that is bad. it is located at the back driver side by the fuel pump. you can unplug it and see if it starts. if so you will need to replace the heater

heater core is leaking needs to be replaced

there is a motor actuator that moves these doors for hot and cold, two separate ones for either side. the motor unit for drivers side is no good and needs new one. replace this and all will be good.

THE MOTOR THE CONTROL THE DOOR FOR VENTS THE GEAR ARE PLASTIC. ON THIS TIME REMOVE THE MOTOR AND CHECK THE DOOR BY HEAND IF DOOR OK REPLACE THE MOTOR CONTROLER.

Check blend door actuator for operation

i had the same problem with my 2000 chevy truck!! i took both hoses off engine and flushed the heater core with water and air frome air compresser,added new coolent and it works perfect!!!! so try flushing your system............