Sag122

I have heat on the passenger side but not the driver side. It's blowing cold air

Rednroll

Not that I'm aware of.....
You likely need to replace your heater core.

Riptide9

If it were a heater core you would smell coolant or not have heat. It sounds like the blend door actuator... cheap and easy fix. Look for one on amazon and think you only need a screwdriver to swap it out

Riptide9

I think this is what you need https://www.amazon.com/Dorman-604-029-Air-Door-Actuator/dp/B00HRSP2A6/ref=au_as_r?_encoding=UTF8&Make=Jeep%7C42&Model=Wrangler%7C356&Year=2011%7C2011&ie=UTF8&n=15684181&s=automotive&vehicleId=1&vehicleType=automotive
Here is a video on how to replace it on a 2011 JK

Suss1173

Rednroll

The symptoms for Heater related problems tends to be the same, but there are multiple causes within the system which can cause those symptoms. I spent well over a year diagnosing my heater problem. I did a lot of research and identified 13 top causes of heater related problems on our JKs and diagnosed each one.

Here is the discussion thread I started at that time which you can use to diagnose your heat problem. My problem ended up being a combination of 3 problems of a leaking radiator, Lower Intake Manifold Leak, and a clogged heater core. The clogged heater core, having the biggest impact to heat performance once it was replaced.
https://www.jk-forum.com/forums/stoc...roblem-339178/

Point being, through the process of my own diagnosis and repairs, I kind of became an expert on the JK heater system, where I feel anyone can take a guess based upon the symptoms you described and that guess will typically be based off of each individual's own personal experience of what fixed their particular problem, which may be the same as yours but in reality it may not and you really need to diagnose and eliminate each of the potential problems until you find the correct problem.

Rednroll

Not true, a bad heater core does not necessarily mean you will smell coolant. The assumption you are making in that statement, which is a valid assumption, is that there is a leak in the heater core, which is a possibility but one of the more common failures of the JK's heater core is that there is casting sand present in the coolant system which eventually gets trapped inside of the HC and causes blockages in the HC. See my diagnostic thread. I had a clogged heater core, and there was no coolant smell present. I performed a dissection of my heater core which shows the problem, where that dissection was performed after multiple advanced reverse flushes of the HC.
https://www.jk-forum.com/forums/stoc...roblem-339178/

Rednroll

See my diagnostic thread and start diagnosing.
https://www.jk-forum.com/forums/stoc...roblem-339178/

Suss1173

Rednroll. Thanks for chiming in and posting the link too.

Rednroll

Based on your symptoms. It seems like your coolant is low since that will cause both higher temp problems, causing your cooling fan to run continuously, as well as cause poor heater performance.
When you 1st get in your JK after it has sat overnight, do you hear a sloshing noise from behind your dash?

The sloshing noise would indicate there is air in the coolant system, and would also cause air to be in the heater core as well. The air in the HC causes the sloshing sound to be heard. Your 1st step of diagnosis would be to check your coolant level to make sure it is full. You can do this by checking the level of the overflow tank and taking the cap off the radiator (while engine is cool), to make sure the coolant is to the top. If not, then you need to fill with proper coolant both in the radiator and overflow bottle to the max fill line and then burb the system to remove the air and then top off the coolant again.

Another potential from your symptoms could be the HOAT/OAT coolant mix problem, which causes gel to form in your cooling system. This will therefore cause blockages both in your radiator (again causing the fan to contnuously run), and your HC (restricting coolant from properly flowing through the HC. Try to inspect your overflow bottle, and look in the bottom to see if there is any gel sitting in the bottom.

Water pump and thermostat is another potential...essentially, at this point, I'm walking you through the list in my other thread and going through the process of elimination.