Heater blowing cold air even when set to high heat

STEPHEN KILLSSMALL

MEMBER
2007 CHRYSLER PACIFICA
4.0L
6 CYL
4WD
AUTOMATIC
157,000 MILES

Heater core started leaking before it was parked couple years ago and everything worked fine before that. Heater core, upper radiator hose replaced along with thermostat and no matter what heat setting or vent combination you use the air remains cold. The engine warms up and radiator hose is hot to the touch while upper heater core hose is hot and lower warm. Curious what I need to check/troubleshoot before I throw more parts at it. TIA

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,268 POSTS

If the heater core hoses are hot, then heat is getting to the heater core, but something is stopping it from entering the cabin.

This sounds like an issue with the blend air door actuator. This actuator is responsible for moving a door in different directions to change air temperature entering the vehicle.

Since you just worked on the vehicle, make sure it is connected. If it is, remove the actuator and see if it reacts to your request to change from hot to cold and opposite.

Here is a link that explains how in general one is replaced:

https://www.2carpros.com/articles/replace-blend-door-motor

If you look at the attachments below, they provide the directions specific to your vehicle.

Before purchasing a new actuator, remove the old one and leave it connected to power, see if it reacts.

I hope this helps. Let me know if you have questions and let me know if this takes care of the problem.

Take care,

Joe

See pics below.

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