If you pull off the heater temp. adjustment knob (yes it just comes off with a little tug) you'll see the control's hold-down nut underneath. My '05 only has 13k miles (bought it used in November) and that nut was very loose on mine. I could tighten it with my fingers -- just to give an idea about how loose it was even with low miles on the vehicle...
Once you get the unit repaired and the nut tigthened -- be sure to either check the nut 1x per year to make sure it stays tight OR do one of these things:
- Take the nut off, slip a locking washer onto the shaft and re-tighten it.
- Get some blue locktite (ace hardware of similiar) and apply to the nut/shaft. This glue's the nut into place and keeps it from working loose.
I took the knob off and the nut was very loose. Can you see the broken wires from there or are they behind the "bolt" thingy? I saw a tiny ribbon like thing above that but I didn't see any wires and I didn't touch it to see if it was loose.
I took the knob off and the nut was very loose. Can you see the broken wires from there or are they behind the "bolt" thingy? I saw a tiny ribbon like thing above that but I didn't see any wires and I didn't touch it to see if it was loose.
Yu are on the right track. the shield comes off to expose the ribbon cable and connector.
Yu are on the right track. the shield comes off to expose the ribbon cable and connector.
LT
Ok, so I can't see it from there. I saw a little ribbon thing above and I was worried when it looked like it was attached. It must be something else. I am taking it to a guy tomorrow who thinks that he can fix it. Keep your fingers crossed for me!
Just to let you know... you guys ROCK! I tool my Highlander in today to be fixed. It was the wire that you told me about. I felt so funny telling the guy what to do to fix it, like I look like I would know how to fix anything. Anyway, he missed it at first but double checked and found the broken wires. I have them in my pocket. It cost me $90.00 compared to the dealerships $900.00 quote.
I am contacting Toyota tomorrow. I think it is crazy that they have not done something about this common problem. I'll let ya know how it turns out. Most likely, nothing will come from it but I am going to try.
Wizzer, fixed the wire in about an hour. To everyone with this problem, please take the time to report to Toyota and the NHTSA so that hopefully we can get this permenatly resolved. When filing a compliant with the NHTSA I found several posts about this problem, the other interesting part is that there were several reports of dashboard fires, I am wondering if this is the root problem of the dashboard fires.
Toyota
Phone: 800-331-4331
Fax: 310-468-7814
Mon - Fri: 5:00 am - 6:00 pm PT
Sat: 7:00 am - 4:00 pm PT Or send correspondence to:
Toyota Motor Sales, U.S.A., Inc.
19001 South Western Ave.
Dept. WC11
Torrance, CA 90501
I am still doing some research on how to handle this complaint. I am still so mad about it because they have had this problem for years now and nothing is being done about it. I could go on & on.
Just joined this community last night, Feb 5th about 7:00 pm. Found the a/c & heater control problem on my `05 Highlander thru Google search. This forum, with pictures, had the exact same problem I was experiencing. Had purchased the Air Mix Servo from a dealership here in the LA area for $ 160.00 because I could see that it was dancing all over the place regardless of where I had the heat knob set. So, it would go from hot to cold to hot to cold randomly. When I'd go around a corner, it would get hot. Thought it was the air mix servo under the dash. When I plugged in the new one late yesterday afternoon, it did the same dance. This told me it was the control module on the dash that was sending the servo confused signals. Sooo, I started searchin the internet for a solution. Stumbled across this site and joined. Found the exact probem, with pictures about 7:30 pm.. I had the dash apart by 8:00 pm and found the broken wire probem right away. Cleaned out the ribbon cable and solder. Found some 20 gauge wire I had and soldered in 3 new wires, then siliconed over the soldering. Re-installed the switch units and put nail polish on the threads of the pots to prevent future loosening. Reinstalled the whole thing this morning and it works like new ! Many thanks to your website and contributors, you just saved me about $ 850.00 to have Toyota do a parts swap that cost me nothing. I will return the air mix servo ... probably with a restocking charge, but still cheap fix for potentialy expensive repair. Thanks again, I will keep watching and posting with any solutions that I come up with.
Thanks Wizzer. Just finished soldering and putting it back together. Heat works great and it is just in time because the temp is 12 F with a wind chill of -20 F. I am so glad that I found this forum.
My hardy thanks to wizzer and dfluitt for their info for fixing the Highlander temperature controller. I was shocked to find out that the controller is a $600 part, and knew there must be a less expensive solution. After I figured out how to get the controller out of the dashboard, and reading your solutions, I had it back and running in less than two hours. The soldering is delicate work, but not too difficult.
thanks wizzer, i've been meaning to post here, but i forgot. i did the fix and it literally saved my life. i had to go to reno nevada for an emergency on 01/01/08 new years day. and a day after i was there, a blizzard hit!!. the heater was the only thing that kept me from freezing because my 2002 highlander got stuck in the snow for 2 hours due to traffic on 80. the windchill and snow combined made the weather feel like 20 below!! the sleet and snow slamming at the windshield at 50 mph and were standing still on the freeway.
i did the fix a week before i went to reno and IT SAVED MY LIFE
THANKS WIZZER, I OWE YOU MY LIFE.
i did go to toyota and they were charging me $750!! for parts only.
I just wanted to post another big THANK YOU!! My wife was having this problem for a while. With the weather being so cold lately I was just about to take it to the dealer. You saved us a nice chunk of change. I took the dash apart and found 2 broken wires. I removed the wire strip and soldered in 3 new wires. Works like a charm. Thanks again.
__________________ 05 Spectra Blue SR5 DC
14" Magnaflow SISO, 2.5" Tuff Country lift, Helo Maxx6 18" rims on 275/70/18 tires, Doug Thorley 512-C headers, debadged, matching tint on front windows, Pioneer AVIC-D3 w/ front & back cameras, Leer 100XQ, more to come.....(I hope!)[SIGPIC]
Hard to believe you messed things up that bad, double check these things...
- The ribbon cable that can be seen thru the clear window in the back of the control cover. Is it connected properly? Might have come loose from moving the cover around?
- Did you have the other rear connectors plugged in firmly?
Thanks I will post a pic later.
The connectors are firmly plugged in, yes the ribbon cable is connected as it was, i even tried inverting it, to be sure I had it correct. Then I righted it and reconected everything, so I reconnected all the connectors 3 times and still only the fan works, all other controls/ lights are out.
I soldered the wires on the back side (where the PCB traces are) so that I did not have to take the board out of the front casing, after soldering it looked like the joints were too close so I filed between them, was very tired and I notched fairly deep into the board between the three joints (2 notches). Thanks for your help, perhaps that board can be repaired.
Did you cut the board in the YELLOW circled area or in the RED circle?
- It does look like some circuit board traces do run under the Yellow area - so inspect there carefully. They might be able to be repaired using some fine strands of wiring to bridge them over?
Another test you could run before removing the control unit from the HL - do the emergency stop hazard lights work? If they don't -- I'd be scratchin' my head a bit, since that circuit isn't part of the repair you did (just something else to try)...
Re: Heater quit... sort of
Re: Heater quit... sort of
, fixed the wire in about an hour. To everyone with this problem, please take the time to report to Toyota and the NHTSA so that hopefully we can get this permenatly resolved. When filing a compliant with the NHTSA I found several posts about this problem, the other interesting part is that there were several reports of dashboard fires, I am wondering if this is the root problem of the dashboard fires.
05 Spectra Blue SR5 DC
Linear Mode
