Highlander blowing hot and cold air alternately

BECKSTER

MEMBER
TOYOTA HIGHLANDER

I am having the same trouble as these 2 with my 2002 Highlander - 3.0L V6 AWD, 80000 miles. I first noticed it this summer when the air conditioner would occasionally blast out hot (and sometimes humid) air randomly then switch back to normal. Now it is doing it with the heat, and I find it less amusing since it is winter in Alberta. Sometimes even hitting a bump in the road will cause the temp of air to switch. As with them wiggling the temp selector to either extreme often helps. Like them, the heat seems to have 2 options, roast your eyebrows off or -30. PLEASE NOTE I HAVE MADE A DONATION and I am very interested in hearing the opinions of some clever mechanics, how to fix it and unfortunately how much it will cost roughly. Thanks very much.

1 Reply

2CARPRO JACK

MECHANIC
11,533 POSTS

First you need to locate the blend door (hot-cold door) be sure that it is moving back and forth when a different temp is selected. Sounds like it may have a bad connection or bad spot on the actuator motor, since hitting a bump jars it to move. Does it do all of these things regardless of how high the fan is blowing?