No heater control?

[jakegator]

Hello, so first off i have a 92 explorer xlt, when i bought the car the only thing that would worked was the main vents (for heat). To pass inspection here i need the defroster to work also, of which it wont switch to. Ive checked the vacuum lines that i know about and they all seem fine... although if anyone has a diagram of how they should be hooked up that would be very nice! Does anyone know how to fix this?

 

[92exp4x4]

Check out the stickies at the top of this forum. There is one for diagrams. There is a diagram for the vacuum system posted and it should help you considerably. Check the vacuum lines closely. I have seen them look ok but have small cracks. They don't show until you bend the line around your finger.

You will probably have to remove the dash to find your problem. There is a vacuum motor on top of the blower box assembly that might be bad. But I would start by making sure the cables and controls are good for the heat/AC system. Remove the control panel from the dash and make sure everything moves and is hooked up properly. If so you will have to remove the dash to inspect the other components. It's not as bad as it sounds, so long as you have the time to do it.

Hope this helps

 

[jakegator]

Thanks for that! I forgot to post back here. It turns out that one vacuum line was disconected but it was just to the recirculation part not the defroster, the problem was the selector lever poped out, just snap it back in and it works.