The 4cyl mileages vary around here, I think based mostly on whether you have 4wd or not.
I have a 2004 I4 2WD. If I drive just me on the highway 330 miles to Minneapolis @75 I get 27~28mpg. Otherwise we normally get 22~24 in mixed city/hwy. In the winter, we'll get down near 20~21 due to snow and cold. Even towing a Uhaul trailer with a washer/dryer I got over 20 on the tank.
But, there are alot of people who report 18-20 mpg. I'm not sure if our O2 sensors are predisposed to failure, or if some other part gets lazy. I'll let you know in a couple years.
As for the original problems, I have them too. Sometimes "all hot" really means "all cold" but 90% hot is 90% hot. When I bought ours with 30k, the knob was loose as hell, so I know one of the wires is probably broken. But finding time to fix this.....
I have been getting 16-17 in town and just returned from a 150 mile trip @62 to 65mph with cruise and A/C and the best I've got is 21MPG. Mine is 2002 4cyl with 71K. Can't figure out why I'm not getting better gas mileage.
Any suggestions would be greatly be appreciated.
Thanks
R Bodiot
I have a 2002 Highlander. The AC control head has gone haywire. The dial no longer "controls" the temperature. Dealership wants around $900. I see some past postings stating that the problem is minor & could easily be fixed. Can someone give me more detailed instruction to try to take care of this? Thank you.
My a/c controls, rear window defroster and seat belt light do not work. I’ve had this problem for a few months now. The a/c control did not work, but the heater did. I was told that the fan is a direct connection whereas the a/c unit has its own module and that is why I am getting heat. I learned how to take apart the a/c control unit from this site, and I am posting my photos of the process as a thanks! By the way I did not find any disconnected wires, the fuses are working fine and there are no codes popping up. I have troubleshot this unit and still no fix. I am having someone look into junkyards for me to see if I can get a good price. So far the lowest I’ve seen is $250 and that was on ebay. But I will be patient. I know I will find something less expensive out there. Besides, who needs the a/c in the winter right? But, I do need the defroster, oh well!
I used a butter knife to pry the cover away from the dash. As soon as you get the first pop, go around the edges and pry off the rest.
Pull carefully for these things can break easy. There are no screws behind this cover. It’s just a simple pull with a little force. You will have to shift to the lowest gear so that you can pull out completely.
Then you will have six hex screws to remove here.
Then some more screws here.
Detach the a/c unit.
Then unscrew the cover to the a/c unit and look for breaks in the wires.
You can see how the fan control is completely separate from the a/c-heater controls. It hooks up directly. Unlike the a/c control and the defroster, they work though the circuit board.
If there are no visible faults then it is possible that the circuit board has gone dead as I am assuming happened with mine. By the way I am female in case you can't tell from the nail polish, lol! Good luck to all who run into the same situation. Any further advice is always appreciated!
Hi all,
See the other thread on this topic entitled "Heater quit... sort of " for detailed information on doing this repair, including photos of the heater control unit once its out of the dash with its back open and the problem wiring shown.
An altogether great fix which should save lots of people lots of money.
I have an '03 Highlander that was giving me the same problem ie the heat would only come on at its hottest and the ac wouldn't come on at all. Thanks to this forum I pulled the climate control module out, found the three wire grouping (one of which was broken) coming out of the back of the temperature control, replaced those wires with more flexible wires and fixed the problem. The hardest part was soldering the new wires to the circuit boards. Also after putting in and removing the unit 4 times because of problems with my soldering, I found the job much easier if you remove the plexiglass window on the back of the unit by loosening the edge with a utility knife. This enables you to install the ribbon wire with ease. The window will push back in place and readhere by pressing it down.
Thanks again you all. You saved me $900 that the Toyota dealer was going to charge me.
Great post!!! My wife has a 2001 Highlander and had even taken it to the local dealer for another problem and asked them to look at this problem. Not only was the problem un-repaired, they left the 10mm bolts completely loose, causing an annoying rattle. The problem finally got so bad, my wife had no heat, so I took it apart last night, soldered in some new wires and re-installed and it works great. Took about 1 hr and a little solder. Saved me many $$$ and wife is happy. Thank you very much!!!
i did this fix last weekend, soldered the 3 wires from the back after removing the
thing from the dash, separating the radio. was only some small number of screws to
remove.
thanks for this!!! saved me a lot of money! and my son who drives it now is happy too.
I own a 01 HI own a 2001 highlander nad was having the same problem with my heater air control panel. After reading some solutions that some of you wrote I went down to the nearest Walmart and bought m3e a $10.00 soldering kit got home and started to fix it heres hoe it went , first put the shifter in low 1 it will give you more room, the pry very carefully with a small flathead screwdriver start on the bottom til you can get your fingers underneath it and start prying and pulling gently!!! all the way up toward the hazard clock area. once you have the trim off there are 6 bolts that need to come off 10mm ands take them off carefully. pull the control unit toward you slowly becayse there are wires plugged in the back for the heater and the radio unit , label them with numbers or letters to remember how they go back. unplug the rtadio cable also this just pulls out, onceyou have the unit off take the brackets on either side be careful because this is the only thing that is holding the radio, then turn the unit facing away from you and take the or 8 smallblack screws off the back of the heater nit and carefully take the backing off it will be held on by wires that donot unplug pull the backing off to the side, take the cold hot center knob off from the front side this just pulls off you will see a nut that holds the potentiometer or dial in place. unscrew this and carefully take the small unit off ther you will find 3 wires conected to the main frame this the problem on or two or even all three wires need to be soldered back in place careful not toy solder these together as it may cross the wires a small tiny bit of solder will do the trick. follow the step backwards and button everything up the way you took it apart and you will have cold air when you want it and hot air when you want it jus take your time you can do it Im no mechanic but i did it and saved me hundreds of dollars I only spent $10.00 and gas money going to the store good luck, rchavez25
My first heat/control system did the intermittent stuff. It would be cold AC and then suddenly blow hot air. I replaced it with a used climate control panel for $680 after paying a local mechanic. Cheaper than the dealer but certainly expensive.
After this second one went out for the same design flaw reason, I found this message board and fixed it myself with some wire I found. It's been working good for two years now.
My sister in law's went bad and I tried to fix it. Even after reincorporating the old wire, it wouldn't work. Any ideas as to why? I heated it a lot with the soldering iron. I'm not a pro yet. Could I have damaged the board or something? Can I fix this somehow?
Don't use the old wire, it's probably broken internally.
Heat the contacts and pull it out. Drill out the holes with a tiny, tiny, tiny (did I say tiny) drill bit. I use a dremel for this. New wire goes in and gets soldered.
If this doesn't work, you'll have to do some investigation with a VOM or have an electronics guy take a look (which will likely still be cheaper than a dealer).
Re: Highlander Heat/Cool control
Re: Highlander Heat/Cool control
Linear Mode
