Blend door will not open

1990
When I move the heat selector to warm, I get about 30% heat 70% outside air.
Not a problem in the summer, but when winter is here ..............
How should the wire to the heat selector be routed in the dash, it seems mine is hung up because it is not moving the blend door to the heat position.

I did have the heater core replaced about 18 months ago, is there a reason that the blend door would have be removed and not re0installed properly?

Thx

Do the diagnostic test and go here decipher the code.

http://www.sccoa.com/articles/climatecontrol.php

The 1990 does not have climate control (typically) and I think what you are referring to is the manual cable.

If the heater core was out and the dash was apart I highly suspect a mechanical problem with the cable. With the glove box open you can observe the motion of the cable to door connection. Watch and see if there seems to be any binding. Does the selector move all the way from warm to cold or does it seem to hang up at some point? It should move all the way to each end of the scale.

duh! I guess he meant cable not wire.

check everything

A mud wasp built a nest in my heater box preventing the door from closing blocking off the cold air. Anything can happen.

Thanks for the tips.
I did mean to say cable, just couldnt think of it at the time.
It appears my cable is caught somewhere.
I can move the door to the stopes manually, but not with the lever.
I did manage to break the connector from the cable to the lever, so now I have a pair of locking pliers holding the door to warm til I fix the cable and connector.