The heater blend door is not run by vacuum. It is run by an electric actuator.
Low on coolant (leak in coolant system) Thermostat stuck open Heater core plugged Temperature blend door actuator failure Vacuum supply to HVAC dissconnected
The heater temp blend valve is located behind the dash assembly. The dash assembly must be removed to gain access.
It does not use a cable. The heater blend door is operated by a electric motor. The complete dash assembly needs to be removed to gain access to the unit.
The heater control valve (temp blend door) is located behind the dash assembly. The dash assembly has to come out to gain access to it.
Remove the dash assembly to gain access to the blend door actuator.
Assuming the blower is working, the reason for no heat could be, low on coolant due to leak in coolant system, thermostat stuck open, heater core plugged or temperature blend control NG.
Yes it could and so could a stuck open thermostat or a plugged heater core or a faulty temperature blend door actuator.
Changing the heater temp blend door actuator requires removal of the dash assembly. Big Job. You will need a shop manual to attempt that one.
The heater temp blend door actuator is located behind the dash assembly, attached to the top of the HVAC box. Unfortunately, the entire dash assembly must be removed to gain access.
The temp blend door actuator is probably at fault.
Control problem, blend door not working are the places to start
The temp blend door is located in the HVAC box behind the dash assembly. The dash assembly must be removed to gain access.