Run a new ignition switch controlled "hot" wire directly to fan motor
The heater core could be burnt out. Make sure your antifreeze is full and your switches on the dash are working. When you move the switch from cool to warm you should be able to hear a difference. If you don't the door/flap may not be moving.
No! Thermostat.
Not knowing what year, make and model you have, I would suspect the heater fan switch and or electrical plug to the switch is at fault.
You have to wire the C4 to a switch.
There are hoses in the engine compartment that go to the heater core. You can remove the intake and out going hoses from the heater core. You have to either block off these hoses or connect them together, depending on the make of the vehicle.
the blown head gasket would make it over heat. but it wouldn't cause the heater to blow cold, it should actually blow hot if that is wat happened
if youre trying to turn the heater on and cold air comes out, then its most likely the heater core
Put in a winter thermostat
Sounds like low coolant or air in the cooling system
The neutral safety switch on this bike is behind the oil filter's aluminum housing. Don't try to bypass the switch as this will make the bike very dangerous in starting.
Depending on the year, make and model check the following............. 1. Trash in blower housing. 2. Defective blower motor. 3. Clogged cabin air filter. 4. Bad blower resister. 5. Bad blower switch.
Check Antifreeze level..make sure there are no leaks under the vehicle.