1999 Jimmy - Heat on High only

[btestacct]

My son's 99 Jimmy has excellent heat. The problem is it won't turn off. Air direction is not a problem as he can direct the heat to any location. Adjusting the temp setting does not change the temp. I removed the knob and verified that the switch was turning. Since I have heat I assume (maybe incorrectly) that it's not a clogged heater core.

There is also a clicking noise coming from the area of the glovebox/airbag. I don't know if it's connected to the heat issue, but wanted it to put it in the post.

Thanks in advance! It's 75 degrees here and with the heat on high I need your help.

[MT-2500]

Could be the actuator or blend door motor.
Remove glove box and locate the clicking.
Make sure it is not a relay.
The blend door actuator is on right top of ac/heater housing.
With glove box out you should be able to see and or feel it.
Is the clicking coming from it?

Check the how to section. For pictures and how to on it.
Lot of good info there.

http://www.automotiveforums.com/vbul...d.php?t=574779

[billindelicato]

if you only get high heat thats the blower resistor thats gone bad...also the in the same general area the clicking you hear is your flasher going on and off due to build up in the switch at the steering colulm there is a complete how to somewhere on here that explains this known issue with the clicking...mine to is clicking but i have a bad back so me getting under there to fix it is just not happening... ill deal with the clicking for now.