no heat front controls or rear

[truckerdan]

I have a 1994 suburban 1500 heater is not working in front or rear and in the front I have no control on the vents it only blows on the floor flashes if I try and change from floor to vents or defrost also blows air on floor while driving with the fan off so seems that the vent is stuck open the rear I have control on vent or floor just will not blow heat just outside temp air I had the same problem with a buick I had and never figured out the problem this is driving me crazy.

[brcidd]

Your mode door electric actuator is either inop- or unable to move the the stuck mode door- or your linkage has come loose- lay on your back, look straight up above gas pedal- see any linkage out of place?