I *think* I found a brand new problem
Thread Starter
8th Gear
Joined: Aug 2005
Posts: 8
Likes: 0
From: Michigan
I *think* I found a brand new problem
For starters I can't thank everyone enough as to how big of a help this site has been. Just bought a 97 about a month ago and have been on here just about every day looking up fixes or ideas for things to do to the car. After the car didn't start a few times, I did the vats bypass that i found compliments of all the members of the site, and haven't had a problem since (in fact the guy i bought it from dropped the price after we experienced the problem during a test drive. lucky for me i had already done my research and wasn't concerned!). Next on the list is getting the oil pressure sensor working, but I've been reading a lot about it and again thanks to everyone here that should be no problem.
Now to stop the rambling, and throw out this new problem i'm having that I don't *think* anyone has come across or addressed on here yet. (my apologizes if I'm wrong and I just wasn't using the right search terms). Periodically while I'm driving, with the heat/AC off, the blower will kick on and start running on it's own, usually the defroster. It'll then fade in and out, on and off, for no particular reason. The only way to make it stop running on it's own is to turn on the heat/ac, even the lowest fan setting, and it will work like normal. What makes this worse is that now the blower is running even when the car is off. However you turn the car on, and it turns off. Turn the car off, take the key out, and yep...the blower turns back on. After hearing it run for about a half hour tonight, i finally resulted to just unplugging the battery till the morning...couldn't figure out how else to stop it.
Anyone have any idea what might be going on here or where i could even start to look?
Thanks in advance for any ideas if ya got 'em
Now to stop the rambling, and throw out this new problem i'm having that I don't *think* anyone has come across or addressed on here yet. (my apologizes if I'm wrong and I just wasn't using the right search terms). Periodically while I'm driving, with the heat/AC off, the blower will kick on and start running on it's own, usually the defroster. It'll then fade in and out, on and off, for no particular reason. The only way to make it stop running on it's own is to turn on the heat/ac, even the lowest fan setting, and it will work like normal. What makes this worse is that now the blower is running even when the car is off. However you turn the car on, and it turns off. Turn the car off, take the key out, and yep...the blower turns back on. After hearing it run for about a half hour tonight, i finally resulted to just unplugging the battery till the morning...couldn't figure out how else to stop it.
Anyone have any idea what might be going on here or where i could even start to look?
Thanks in advance for any ideas if ya got 'em
Race Director
Joined: Mar 2004
Posts: 12,466
Likes: 886
From: Fort Wayne IN
2025 C5 of the Year Finalist - Modified
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Do you have the manual or automatic HVAC controls??? If it's manual.......I've got no clue. If it's the automatic HVAC, it might be something short circuiting in the unit itself....maybe try unplugging that and seeing if the problem persists, or finding someone to swap out with for testing purposes.
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
If its the automatic HVAC system, I heard there is a reset procedure for that, but I doni't have a clue what it is. Its been posted in here before though.
Le Mans Master
Joined: May 2006
Posts: 5,987
Likes: 18
From: DuBois PA
St. Jude Donor '11-'12-'13-'14-'15
If you're still having problems after the reset, try this troubleshooting procedure;
DEFINITION: Blower motor is on at any selected speed.
1
Was the blower motor system check performed?
--
Go to Step 2
Go to HVAC Blower Control (CJ2) System Check
2
Disconnect the HVAC programmer module connector.
Turn the ignition switch to the RUN position.
Is the blower motor on?
--
Go to Step 3
Go to Step 4
3
Turn the ignition switch to the OFF position.
Disconnect the blower motor control module connector.
Connect a test light between terminal C of the blower motor control module connector and a known good ground.
Does the test light illuminate?
--
Go to Step 5
Go to Step 6
4
Replace the HVAC programmer module.
Is the replacement complete?
--
Recheck System Operation
--
5
Connect a test light between terminal B of the HVAC programmer module connector and a known good ground.
Does the test light illuminate?
--
Go to Step 6
Go to Step 5
6
Locate and repair a short to B+ in CKT 63.
Is the repair complete?
--
Recheck System Operation
--
7
Replace the blower motor control module.
Is the replacement complete?
--
Recheck System Operation
--
Also, download the DVD maintenance manual;
http://forums.corvetteforum.com/c5-t...al-on-dvd.html
And yes, this is a new one.... congrats!
DEFINITION: Blower motor is on at any selected speed.
1
Was the blower motor system check performed?
--
Go to Step 2
Go to HVAC Blower Control (CJ2) System Check
2
Disconnect the HVAC programmer module connector.
Turn the ignition switch to the RUN position.
Is the blower motor on?
--
Go to Step 3
Go to Step 4
3
Turn the ignition switch to the OFF position.
Disconnect the blower motor control module connector.
Connect a test light between terminal C of the blower motor control module connector and a known good ground.
Does the test light illuminate?
--
Go to Step 5
Go to Step 6
4
Replace the HVAC programmer module.
Is the replacement complete?
--
Recheck System Operation
--
5
Connect a test light between terminal B of the HVAC programmer module connector and a known good ground.
Does the test light illuminate?
--
Go to Step 6
Go to Step 5
6
Locate and repair a short to B+ in CKT 63.
Is the repair complete?
--
Recheck System Operation
--
7
Replace the blower motor control module.
Is the replacement complete?
--
Recheck System Operation
--
Also, download the DVD maintenance manual;
http://forums.corvetteforum.com/c5-t...al-on-dvd.html
And yes, this is a new one.... congrats!
Melting Slicks
Joined: Oct 2007
Posts: 2,798
Likes: 8
From: It's true money can't buy happiness, but it is more comfortable crying in a Corvette than on a bicyc
St. Jude Donor '13
For starters I can't thank everyone enough as to how big of a help this site has been. Just bought a 97 about a month ago and have been on here just about every day looking up fixes or ideas for things to do to the car. After the car didn't start a few times, I did the vats bypass that i found compliments of all the members of the site, and haven't had a problem since (in fact the guy i bought it from dropped the price after we experienced the problem during a test drive. lucky for me i had already done my research and wasn't concerned!). Next on the list is getting the oil pressure sensor working, but I've been reading a lot about it and again thanks to everyone here that should be no problem.
Now to stop the rambling, and throw out this new problem i'm having that I don't *think* anyone has come across or addressed on here yet. (my apologizes if I'm wrong and I just wasn't using the right search terms). Periodically while I'm driving, with the heat/AC off, the blower will kick on and start running on it's own, usually the defroster. It'll then fade in and out, on and off, for no particular reason. The only way to make it stop running on it's own is to turn on the heat/ac, even the lowest fan setting, and it will work like normal. What makes this worse is that now the blower is running even when the car is off. However you turn the car on, and it turns off. Turn the car off, take the key out, and yep...the blower turns back on. After hearing it run for about a half hour tonight, i finally resulted to just unplugging the battery till the morning...couldn't figure out how else to stop it.
Anyone have any idea what might be going on here or where i could even start to look?
Thanks in advance for any ideas if ya got 'em
Now to stop the rambling, and throw out this new problem i'm having that I don't *think* anyone has come across or addressed on here yet. (my apologizes if I'm wrong and I just wasn't using the right search terms). Periodically while I'm driving, with the heat/AC off, the blower will kick on and start running on it's own, usually the defroster. It'll then fade in and out, on and off, for no particular reason. The only way to make it stop running on it's own is to turn on the heat/ac, even the lowest fan setting, and it will work like normal. What makes this worse is that now the blower is running even when the car is off. However you turn the car on, and it turns off. Turn the car off, take the key out, and yep...the blower turns back on. After hearing it run for about a half hour tonight, i finally resulted to just unplugging the battery till the morning...couldn't figure out how else to stop it.
Anyone have any idea what might be going on here or where i could even start to look?
Thanks in advance for any ideas if ya got 'em
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
The auto HVAC control must have a electronic blower motor controller in the car somewhere. I don't have access to the car or manuals this weekend so I can't help much. However, I know other GM cars have a module that controls the blower and if it goes bad the blower won't turn off. The C5 probably has a similar thing, if not it'd be built into the main dash module. If you don't figure out the problem by tomorrow night I can see what the service manual shows.
Peter
Peter
