Hello forum,
I just bought a 98 jimmy and found that i can not get warm air to come out the dash vents only cold. I have heat on the floor and on the defrost.My heater core hoses are both hot and my thermostat is ok. I have never had a vehicle with climate control before so i could be doing something wrong but i dont know.I dont know if pulling the rdo fuse will help or not. Any one?? Oh and I've been through the dreaded intake gasket problem on the 97 blazer i had before so i dont beleive thats the problem this time.Thanks

Hello forum,
I just bought a 98 jimmy and found that i can not get warm air to come out the dash vents only cold. I have heat on the floor and on the defrost.My heater core hoses are both hot and my thermostat is ok. I have never had a vehicle with climate control before so i could be doing something wrong but i dont know.I dont know if pulling the rdo fuse will help or not. Any one?? Oh and I've been through the dreaded intake gasket problem on the 97 blazer i had before so i dont beleive thats the problem this time.Thanks

GIVE THE OLD PULL FUSE A TRY.
Confirm good vacuumn from engine to heater controls?
Any HVAC codes in body module?
Does the dash vent have good air flow out of it?

Ok i pulled the fuse replaced it and i noticed that i had hot air for a few seconds then it went to cold. I got on the internet and found a few things i hadnt seen before .My problem is the blend door motor behind my glove box.When I start the jimmy it moves the blend door from hot to cold and gets stuck on cold.Since i dont have the time right now to replace it and its getting cold out I put a bandaid on it for now.Within the first few seconds or so after i start the jimmy up i pulled the plug on the blend door motor so it stayed on heat and now I have heat out the yin-yang.Keep in mind that when you do this you lose the climate control.If i get to hot i crack a window or turn down the fan. I found a pretty good pic of this motor location so ill try to post it here. you need kind of skinny hands to unplug it unless you remove things.Thanks for the reply MT-2500.I hope what I found helps someone.Thanks to the original pic poster it really helped me out.http://i16.photobucket.com/albums/b40/JoshB_/relay2.jpg

Ok i pulled the fuse replaced it and i noticed that i had hot air for a few seconds then it went to cold. I got on the internet and found a few things i hadnt seen before .My problem is the blend door motor behind my glove box.When I start the jimmy it moves the blend door from hot to cold and gets stuck on cold.Since i dont have the time right now to replace it and its getting cold out I put a bandaid on it for now.Within the first few seconds or so after i start the jimmy up i pulled the plug on the blend door motor so it stayed on heat and now I have heat out the yin-yang.Keep in mind that when you do this you lose the climate control.If i get to hot i crack a window or turn down the fan. I found a pretty good pic of this motor location so ill try to post it here. you need kind of skinny hands to unplug it unless you remove things.Thanks for the reply MT-2500.I hope what I found helps someone.Thanks to the original pic poster it really helped me out.http://i16.photobucket.com/albums/b40/JoshB_/relay2.jpg
You are welcome.

If you have heat and cold on flood and defrost it may be other problem than blend door.

Good luck

No im pretty sure the blend door motor was my culprit. I have heat everywhere now. I have more heat than I know what to do with now lol.

No im pretty sure the blend door motor was my culprit. I have heat everywhere now. I have more heat than I know what to do with now lol.

Good luck