The temperature control on my 2004 Toyota Highlander keeps switching by itself from hot to cold and hot again. I have to actually turn the ac on even when the outside air coming in is moderate because the temperature control will switch by itself to hot and I can't switch it off. This occurs every time I drive and more so when I go over a bump or make a turn. I turn the vent on for outside air, but the temperature control gets locked on to hot and I can't turn it off. I have called the dealer and they have said that it would cost around $1000 to fix it. They want to replace the whole control unit. I have read various forums of numerous owners having this same issue. It seems to be a problem with Toyota not leaving enough slack in a ribbon cable with 3 connections that connect from the circuit board to the control knob. The wires break off from the soldering on the knob. This sounds like a known defect to me that Toyota is aware of, but chooses to ignore. Apparently a cheaper fix is to re-solder the cable, but they refused to do that. I think they should be fixing this for free. This is just another example of Toyota ignoring known issues with their vehicles.

- Castro Valley, CA, USA