the roller dial can be adjusted where the front window heat cannot , two different types of control,
it needs a new blower motor resistor ....
It usually shouldn't, but if it does, it should only stay like that for a few moments.
A bad control switch can cause your 2003 Nissan Sentra heater blower to stay on. The motor or a bad sensor can also cause the heather not to work properly.
follow the plug from the blower motor. It should lead to another plug on top of your heater core housing.There should be three bolts securing the plug. Remove them and replace the part. I don't know what it is called.My 1988 eldorado did the same thing. Works fine now though.
Common causes, blower motor resistor, blower motor, wiring or controls
Recommend you check the blower motor resistor.
bad blower switch located behind blower control.
A common cause for this is a burned out blower resistor. Tech JK --------------------------
if you are talking about a radiator then yes it is supposed to stay on.
Could be a bad actuator switch which operates the door flap, therefore allowing air to constantly pass across the heater core, hot into the cab. The actuator is located behind the blower motor, which is under the glovebox.
There could be several reasons why your heater won't stay on, such as a faulty thermostat, clogged air filters, or a malfunctioning heating element. It's best to have a professional inspect and repair your heater to determine the exact cause.
The heater may not stay on due to issues with the thermostat, a clogged air filter, a malfunctioning heating element, or a problem with the electrical connection. It is important to troubleshoot and address these issues to ensure the heater functions properly.