Heater only works on 3 and 4 setting

Check fuse and relay as mentions in the link. Also the BCM is involved with climate control in which case you will need an auto electrician with a pro grade scan tool computer.

https://www.google.com/search?q=2003+liberty+heater+fan+does+not+work


Relay 33 in the Power Distribution Centre

Fuse Box Diagram Jeep Liberty / Cherokee (KJ; 2002-2007)

https://fuse-box.info > jeep > jeep-liberty-kj-2002-2007...
Here you will find fuse box diagrams of Jeep Liberty 2002, 2003, 2004, 2005, 2006 and 2007, get information about the location of the fuse panels inside the ...

That is a whole lot of issues that needs an auto electrician and a pro grade scan tool computer. We have a pro electrician here @Jeff Armer and hopefully he will chime in. Sounds like a communication issue with BCM and ECM which I think is combined into a TIPM.

https://www.google.com/search?q=jeep+liberty+p0501

If you disconnect the battery, you have to reset the anti-theft system.

https://www.google.com/search?q=jeep+liberty+tipm+reset

How do i reset the Jeep Liberty alarm? - Vehicle History

https://www.vehiclehistory.com > questions > how-do-i-...
To reset the Jeep Liberty alarm, press the control door-lock button on the keyless entry fob. Open the side door of the cab. Leave all doors closed for around ...
3 answers · Top answer: If You want to reset the alarm on the Jeep Liberty then You will need to fol

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no idea to be honest earlier jeeps had then at the front of the wing down below as i remember ?? newer one would i imagine be in the electrical box under the bonnet near the battery

Jeep Liberty heater not blowing hot air Questions & Answers ...

www.fixya.com > ... > heater not blowing hot air > Cars & Trucks > Jeep

Jeep Liberty cars & trucks heater not blowing hot air questions and answers. Ask your Jeep heater ... My 2005 Jeep Liberty will not blow heat through ... properly.

jeep liberty 2002 heat problem/hvac box issue - YouTube

? 3:12
https://www.youtube.com/watch?v=xf22fvcN1hU
May 28, 2013 - Uploaded by Joffre richer-desroches
Joffre richer-desroches. ... How To Install Replace Engine Coolant Thermostat and Housing 3.7L 2002 ...

You can get the silicone grease at automotive and hardware stores. Apply to rubber seal on cap about every 2 to 3 months. This will ensure a seal so that the engine light doesn't come on. Worked great on My 2008 Liberty.

under the glove department is a heater motor resistor you can look the part up on ebay , it located under the glove box ,, place in a cut out , you have to look carefully but it is there ...i beleave one screw holds it in ,, it a easy fix ... just swap the old part for the new ..

probably a burned resistor. Please see my tip at http://www.fixya.com/cars/r6234839-doesn_t_heater_or_air_conditioner_blow . These are generic instructions. If you get stuck or need specific instructions for your car, please get back to me with model, year and engine info.
Not sure where your resistor is--somewhere along the heater box tho. Looks like the below picture with wires coming out.

check for wire terminal pushout or spread terminal at connector where o/2 plugs into harness

sounds to me like your blower resistor is bad.it happened to a friend of mine,but his would only work on high.i replaced it for him and now all speeds work like new.hope this info helps.good luck and take care, manny

What do you mean you "went through a car"??? Did you crash???
Generally one speed being "out" is caused by a burned out relay or resistor pack. Check those!!!