Have Jeep Questions? Ask a Jeep Repair Expert for Answers
Hello and welcome to JustAnswer.
My name is Vlad.
As far as I know, you will need an appropriate scan tool to check HVAC system for trouble codes.
Make sure your coolant level is OK and check both hose going to the heater core near the firewall. They should both be hot to touch when engine is running at normal operating temperature.
If on ly one is hot or warm, then you have a problem with coolant circulation.
It is possible that you have a problem with a blend door actuator but it is quite unlikely that both driver and passenger side failed at the same time. Also, I had once a faulty actuator on the driver side and I can tell you that the blower motor will work and then stops for some seconds ( like somebody pause it) and then continue to work when there is a problem with actuators.
Did you check heater hoses ? You mentioned radiator hoses that is not the same.
I mentioned blower motor as interrupted operation of the blower motor would indicate an actuator failure.
If the heater core is blocked, there will be no circulation so one heater hose will be warm or hot and another will be cool or slightly warm.
Smell and fogging only occurs when teh heater core is leaking.
If it is really clogged , then you can try flush and back flush it and sometimes it helps.
Anyway, before you do anything you should determine what is wrong.
Just check both hoses that going towards the firewall. They are about 5/8" size.
Engine must be running at normal operating temperature and they should be really hot if coolant circulates properly via the heater core.
As long as your HVAC control panel works and you control blower speed and air direction, you should not worry about relays or fuses.
At this stage you need to determine whether hot coolant flows via the heater core or not.
If it flows OK, then there is a problem with blend doors or actuators.
If it does not flow, it is a cooling system problem .
I am in Australia and we have RHD Jeeps here so it could be a bit different location for your LHD market.
As far as I remember both hoses ( you can see them) go into the firewall almost in the middle of the engine compartment ( maybe a bit closer to the LH side of the car). There is a windshield wiper grill and both hoses "make a turn" under that grill ( you can't see it unless grill removed) and then connect to the heater core outlet and inlet pipes.
It is late night here, will check your reply tomorrow. Thanks
They should be really hot when your engine is at norm operating temperature.
If I remember correct, I once managed to check heater core aluminium pipes from inside of the car from underneath of the dash. I believe it was on the RH side but you will need to remove lower sound insulation panel ( just clips) and then have a look with a good flash light closer to the center. If you can see two silver pipes, then feel them while engine is running.
Hi I am just checking if my answer has helped you in anyway or if you might need more assistance.
Let me know how it goes.