my 98 classic heat and ac work just fine but it only works on high any ideas?

 

Most likely the heater control resistor board has fried. It is not an uncommon problem, but one easily fixable.

The part is located behind the glovebox and slightly down attached into the duct work. Look for a somewhat rectangular looking item screwed into the duct with a plug connected to it. Remove the two screws and plug and it should come right out. When you look at it, it will look like some circuitry with some windings and a couple electronic components. It likely will look all rusty if it has gone bad. It is susceptible to moisture and there is plenty in the ducts. Not the best design.

They are not expensive and should be available at most auto parts stores.

 

lll check it out thanks

 

Can you post a pic of it

 

Blower motor resistor should be above passenger feet area on HVAC box.

 

http://www.cherokeetalk.com/forum/f6...acement-11133/

 

Rock auto had them for something like 12 bucks dorman brand, I just put one I. Three weeks ago In the 98, works like a charm no problems.