Expert: Roland Finston - 8/4/2011

Question
QUESTION: 2004 concorde limited.  Ran diagnostics.  #23 error.  I know it is blender door code.  Only front vent not blowing.  Sometimes goes from cold to hot.  Fan doesn't seem to work great...very light to full power.

ANSWER: Hi Susie,
I have to say that other than what I suggested earlier about the fan power module, I don't see the unit recognizing an issue with the air distribution door, which would be a 24 code. So maybe checking out the fan motor for dirt in the housing or oiling the motor bearing would be the first thing to do. It is located on the underside of the unit at the right hand end. Remove the screws and it should drop out.
Roland

---------- FOLLOW-UP ----------

QUESTION: When I started the car this morning, the vents in the front worked! Then it stopped again.  Also, when I am doing the diagnostic, at 75, it blows cool until I set the thermostat to high, then it is hot.  Should I still start with the blower module?

ANSWER: Hi Susie,
If by 'stopped' you mean the blower slowed or stopped, then yes. If the blower remained the same speed and it seems to be working on all speeds, then no. The air distribution issue is a separate matter from the blower output speed. If the air is blowing out of other vents than the selected front vents then there is an issue with the 'mode' door actuator. So let the specifics of the situation be your guide.
Roland

---------- FOLLOW-UP ----------

QUESTION: This maybe a shot in the dark, but this all started when the battery was changed the other day...any thoughts?  Also, I was going to try to pull the M1 fuse and see if it was that.  I didn't have a fuse puller, so I just closed up the compartment and this morning I had no readouts anywhere.  I hit the cover and they went on again.

Answer
Hi Susie,
I don't see a relationship of the battery being changed to anything related to the blower motor or the ac function either. The M1 is of course that which supplies power to the functions that are needed when the ignition is off. So if that fuse were flaky/poorly connected then that could impact the instrument cluster amd also I see that it is one of two fuses that power the automatic temperature control panel. So remove that fuse and observe it closely for a subtle crack in its wire or poor contact surfaces with the socket into which it fits.
Roland
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