CUCV heater problem

[airbornebandsman]

OK so my heater stopped working. The low coolant light is on (yes there is coolant in the radiator and reserve) but I wouldn't think that would have anything to do with it. Could it be a fuse and if so where is the fuse box?

 

[ida34]

By not working do you mean the blower motor is not blowing or it is blowing cold air? If it is blowing cold air then I would check the coolant again. When the coolant gets low the first thing that happens is no coolant goes to the heater core since it is about the highest point in the system. The fact that the low coolant light is on also points to this fact. When it is running and up to temp are the heater hoses warm to the touch? If the blower motor is not blowing air first check the fuse. It is under the dash but I do not remember which one it actually is. Just look over all of them for a blown fuse. It is to the left of the steering column as you sit in the truck facing forward. If the fuse is good then check for voltage at the motor with the fan switch on high. If there is 12 volts there then the motor is probably bad but check for a good ground before replacing it. If the blower motor only works on high and no other settings then the blower resister is bad. It is attached to the heater case and drops the voltage to the motor to provide medium and low fan speeds. If you do not have power to the motor then check for power at this resister. No power there then check the switch for power.

 

[airbornebandsman]

yeah the blower motor is not blowing at all, the low coolant light is staying on even though the radiator and attached tank are full.

 

[ida34]

The heater blower system is pretty simple.


Line to fuse (switched through the ignition switch)
fuse to switch
switch to heater resister
heater resister to heater.

Only five components to go bad or the wiring in between.