99 c5 ac poor venting & weak
Thread Starter
Intermediate
Joined: Mar 2008
Posts: 25
Likes: 0
From: Kahnawake PQ
99 c5 ac poor venting & weak
Having a problem with the AC venting on my 99 C5 Convertible.Not blowing very strong.Cold but not strong.When on Max, the fan seems like it is on a lower setting.Concluding one of the venting doors not working properly, possibly the vac line that requires access by removing the RH inner fender and replacing the line ? Can someone please direct me to a thread with some detailed info on possible causes and fixes ? Or offer some tips ? Thanks for your help in advance.Much appreciated.Getting hot out there and I need some AC LOL !!
Burning Brakes
Joined: Feb 2012
Posts: 901
Likes: 2
From: Palm City Fl
Have you checked for any HVAC codes? If you have codes try resetting them, write them down first though. If you don't have any codes you might try disconnecting the - battery lead for a few seconds. The mix doors will then go to full open and full closed to relearn their stops. My 99 gave me fits for a while. Ended up taking the whole dash apart just to find that the mix doors were working fine. 
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
You MUST do it this way if recalibrating is truly the problem:
Re-Calibrating Actuators-----
Use the following steps to perform the calibration update:
1. Turn OFF the ignition.
2. Remove the battery positive voltage circuit fuse of the HVAC Control Module (fuse #27).
Important
The module memory will not clear if the battery positive voltage circuit fuse is installed in less than 60 seconds.
3. Wait 60 seconds.
4. Install the fuse.
I have heard some people have had to do it several times to have it "take".
Re-Calibrating Actuators-----
Use the following steps to perform the calibration update:
1. Turn OFF the ignition.
2. Remove the battery positive voltage circuit fuse of the HVAC Control Module (fuse #27).
Important
The module memory will not clear if the battery positive voltage circuit fuse is installed in less than 60 seconds.
3. Wait 60 seconds.
4. Install the fuse.
I have heard some people have had to do it several times to have it "take".
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Thread Starter
Intermediate
Joined: Mar 2008
Posts: 25
Likes: 0
From: Kahnawake PQ
Thanks for the advice.First thing I thought of was checking the vac line on the intake ? I am not sure but I will check again, but thought that the flow was not working on defog mode.Will chek fuses too.