What would cause a 1996 Dodge ram heater gets warm but when you turn Blower up it goes cold?
If the engine is getting up to normal temp, the heater core might be plugged. Heater core is not plugged and normal operating temp!
What would cause a vehicle heater to blow warm air when blower on low but blow cold when blower turned up?
Could be, heater blower motor has failed. blower motor fuse is burned out. blower motor speed resistor is burned out. blower motor switch is bad. or, if the blower motor works but you have no heat it could be, cooling system is low on coolant. thermostat is stuck open. heater core is plugged. temp blend door actuator is faulty.