A/C Problem in 1999 C5
Thread Starter
Cruising
Joined: May 2007
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A/C Problem in 1999 C5
I'm hoping someone can help me. For about a year, my A/C has been acting erratic along with a few other electrical problems. I saw the postings about the gounding issues and found them very helpful, although I still can't resolve my A/C issues.
When I press the mode button on the head unit, the head unit display changes properly. However, no matter what mode I am in, the air is always exclusively blowing through the defroster vents. I can not dirrect airflow any where else.
I also noticed at night, the dash illuminations occasionally flickers. Could this be related?
Any ideas? Thanks in advance.
When I press the mode button on the head unit, the head unit display changes properly. However, no matter what mode I am in, the air is always exclusively blowing through the defroster vents. I can not dirrect airflow any where else.
I also noticed at night, the dash illuminations occasionally flickers. Could this be related?
Any ideas? Thanks in advance.
Melting Slicks
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From: Rockford Illinois
Race Director
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From: Saint Augustine, FL
Mid-TN Events Coordinator
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
The actuators only control the cold/warm settings. The problem you are having is vacuum related. Take a look at your battery, I would be willing to bet it is/has leaked acid. If so, there is a vacuum hose under the battery tray, and it more than likely has been eaten up by the acid. This hose is what pulls vacuum on your HVAC controls. Also, it could be the hose has come loose of the back of the intake manifold. It's really hard to get to, and may require removal of the intake manifold if it has fallen off.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You have a vacuum issue!! You will need to start at the back of the intake manifold where it connects to the MAP sensor fitting and follow the small black plastic hose into the wiring harness and then where it exits down in the passengers fender well area.
There it connects to a black plastic vacuum reservoir and then splits off to the HVAC and the A.I.R. system under the drivers headlight.
Figure out why you don't have vacuum and you will solve a whole host of issues!
Bill C
There it connects to a black plastic vacuum reservoir and then splits off to the HVAC and the A.I.R. system under the drivers headlight.
Figure out why you don't have vacuum and you will solve a whole host of issues!
Bill C
Team Owner
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
HTH
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Thread Starter
Cruising
Joined: May 2007
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You have a vacuum issue!! You will need to start at the back of the intake manifold where it connects to the MAP sensor fitting and follow the small black plastic hose into the wiring harness and then where it exits down in the passengers fender well area.
There it connects to a black plastic vacuum reservoir and then splits off to the HVAC and the A.I.R. system under the drivers headlight.
Figure out why you don't have vacuum and you will solve a whole host of issues!
Bill C
There it connects to a black plastic vacuum reservoir and then splits off to the HVAC and the A.I.R. system under the drivers headlight.
Figure out why you don't have vacuum and you will solve a whole host of issues!
Bill C
Thread Starter
Cruising
Joined: May 2007
Posts: 10
Likes: 0
Sure enough, battery acid....
In pics 7677 and 7679, is this the vacuum hose? If so, I can't find the other end?
Pic 7681 shows a tube that I found just dangling in the passenger fender. Is this a drain tube? Should it be split like that?
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The giant black hose with the split is the cowl drain! Its suppose to look just like that!
Here is the rest of the pics for vacuum line troubleshooting:
Manifold connection:
Resivour in fender well:
HVAC vacuum connections:
Hope this helps!!!
BC
Here is the rest of the pics for vacuum line troubleshooting:
Manifold connection:
Resivour in fender well:
HVAC vacuum connections:
Hope this helps!!!
BC
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I go to Carlsile Pa every year and if there is a part that i have not seen before or a part that has been giving us problems,,,I take pictures of it. Believe me it sure helps explain stuff!!
The Corvette museum also has some very cool tings to take pictures of. Their rolling C5 chassis is very detailed and I have LOTS of pictures of that one! Too bad it just an early C5 chassis. They should have a later C5 on display.
Every repair or project is well documented also!
BC
The Corvette museum also has some very cool tings to take pictures of. Their rolling C5 chassis is very detailed and I have LOTS of pictures of that one! Too bad it just an early C5 chassis. They should have a later C5 on display.
Every repair or project is well documented also!
BC
