Can't find blend door in HVAC
 

A/C blows very cold when engine is cold, after warm-up A/C air is only cool. Compressor works ok, refrigerant pressure is normal. Vacuum operated doors that direct air flow to various vents operate properly. The Hot-Cold control operates the blend door via a cable, but I can't find it. I've removed the glove box and I see a black plastic container in which I suppose are the A/C evaporator, heater core, etc.

How do I proceed to go further inside to check the blend door operation?

Has anyone else had these same symptoms?

Thanks for any tips,
Alan

Thanks for posting the diagram, ymeski56. I have several good schematic diagrams, I just can't get inside the unit to access the moving doorflaps and check my cable connection to the blend door.

i missed the year model of truck ... my father inlaws got a 92 and has the round knobs and that flap hung and froze me til i pulled glove box and worked cable and used priers to pulled it shut it was top air box to the left hard to see had too feel for it... oh this was wintertime too ....

my bad sorry but what is ambient temp at vent when truck is say warmed up, and how do you know refrigerant pressure is normal...you using high and low pressure gauges or that gauge that advanced auto has blue hose and color reading gauges green is normal red is low etc....most equipment and auto blow cold when engine is cold or hot ....im thinking youre low in freon but hey im human

Today it's working fine. Outside temp 87 degrees, a/c blows out 41 degree air. Even after engine warm-up it's cold. I'm not touching the temp control until this fall. "If it works don't fix it." Thanks to all who replied.
Alan