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2006 jeep liberty heating problem

Hi,
I replaced my heater core and the blower.
The heat still blows cold. Temp gage is normal…
and I added coolant.
Any ideas?

Have you checked for proper blend door operation?

Tester

Not yet, will do thanks…anything else I should check?

Do you think it could be the thermostat???

Unlikely the thermostat since you stated temperature is normal.

If the temp gauge shows normal engine temperature, then no.

Tester

Here’s what the blend door actuator looks like.

https://www.rockauto.com/en/moreinfo.php?pk=10072892&cc=1432214&jsn=386&jsn=386

This actuator moves the blend door and determines if hot or cold air enters the cabin.

If the blend door actuator doesn’t work, it could be actuator itself or a problem with the climate control module.

Tester

You won’t get any heat if the heater core isn’t hot. Are you able to verify the heater core is actually getting hot? A couple ways I can think of to do tha

  • measure the temperature of the coolant going into and out of the core from the engine compartment side. You could use a thermometer, thermo-couple, thermistor, but the easiest would be one of those laser-guided infrared temperature measuring gadgets. if hot coolant is flowing in and out of the heater core like should be happening, both hoses going through the firewall should be very hot and close to the same temperature once the engine is warmed up to normal temperature

  • even better, measure the temperature of the heater core itself, if you can get access to it from under the dash.

If the heater core is getting hot but you don’t get any hot air coming out to warm the cabin, then the problem is the air flow path, not coolant. If you can change the mode to use either fresh air or recirculated air, see what that does. try all the settings, you may find a clue to what’s wrong with the air path that way.