I do not have any heat in my blazer, the fan blows but no heat

check and test with a meter the fan --fan speed control module [ attached to fan housing ] --switch and relays ---

Sounds like the Blower Motor Resistor. The range from 10 to 75 dollars depending on what kind of vehicle. Pretty easy to change.
Blower Motor Resistor Repair Heater Fan Speed Control Chevy Blazer GMC...

blower motor needs to be replaced. tap on blower with rubber hammer of hand key on, fan switch on. you will see fan start to operate..

Where do I find the ground for fan

I would check for a bad connection on the blower motor resistor.Its located on the passenger side mounted on the heat duct with 2 screws.Turn the ignition and fan switches on then wiggle and pull on the connector usally if the resistor has a poor connection it will comw on.These resistors get hot and sometimes they melt the connector causes it to loose its connection.

change the heater relay fuse or the reastate that makes your fan go to high or low

as ur blazer is more than 10 years old u should be able to get step by step info. from autozone.com hope this helps

Check the water pressure in your engine system. You could have a cracked radiator core, or tank, or a leaking water pump, or hose, or a weak radiator cap that will not allow the pressure to build up in your engine and move the heat around as is required.

I doubt the heating problem is related to the battery indicator unless the fan belt is slipping QUIETLY, but that will not last long, as you will burn through the belt soon.

If you got a good battery and a good alternator then check your fan belt. Remember, check the pressure of the water in the engine block to deal with the heat problem.

blower control modular,,are u engaging while moving or stopped.

the unit were you turn on the fan leaks vacuum which causes the vents not to blow properly the unit is not expensive for it is plastic comes with fan switch ex..