I get error codes 110 and 138 using the diagnostics for the climate control. Does anyone know what the error codes mean? Also the external temp. reading seems to read about 50 degrees low, then creeps up after about 10 minutes, this prevents the A/C from coming on even if it is hot outside. The A/C seems to kick in when the temp. reading hits 47 degrees.
Can anyone help me here ??

check this post:

http://www.automotiveforums.com/vbulletin/showthread.php?t=351294&highlight=a%2Fc

Sounds like a bad ambient (external) temp sensor or connection. Both codes are old with the prefix 1. Clear the codes and see if they come back, if so, repair the problem with the external sensor. Code 138 is "failure to communicate" with the PCM more than likley from the ambient air sensor.