Air Conditioner stuck on?
Thread Starter
Cruising
Joined: Mar 2005
Posts: 11
Likes: 0
From: Fresno California
Air Conditioner stuck on?
I recently went on vacation for about 3 weeks, well when I got back I realized that I forgot to disconnect my battery to prevent it from going dead.
So I replace the battery after finding the old one wouldn't hold a charge anymore, when connecting the new battery I hear the AC system start up, well that's weird... so I start up the car and try to turn it off, I pushed every button on the panel and it would not turn off, the only thing I could do was switch it from vent to floor. Turned on and off the car a few times, AC system is still going. So I disconnected the battery again, reconnected it, still going. I currently have the battery disconnected so not to cause any further problems.
Anyone have any idea what is going on?
Edit: Forgot to mention, the Vette in question is an '86
So I replace the battery after finding the old one wouldn't hold a charge anymore, when connecting the new battery I hear the AC system start up, well that's weird... so I start up the car and try to turn it off, I pushed every button on the panel and it would not turn off, the only thing I could do was switch it from vent to floor. Turned on and off the car a few times, AC system is still going. So I disconnected the battery again, reconnected it, still going. I currently have the battery disconnected so not to cause any further problems.
Anyone have any idea what is going on?
Edit: Forgot to mention, the Vette in question is an '86
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
two things
You will always hear the A/c clutch click in when you reconnect the battery.Can be killed by pressing off on A/c panel
Most likely fan blower control module has gone.This gets power direct from the battery , so can start fan at random if faulty.
Connect battery , if blower fan runs ,disconnect fan connector at front of heater housing by fan motor.
The control module is in the top of the heater unit, towards firewall from top A/c line. , two wire loom plugs and 3 screws.The unit is inside the housing so the heat sink is coled by the airflow.
Only way I founf my prob was by fan randomly starting up with ign off when I was in the garage.WTF
You will always hear the A/c clutch click in when you reconnect the battery.Can be killed by pressing off on A/c panel
Most likely fan blower control module has gone.This gets power direct from the battery , so can start fan at random if faulty.
Connect battery , if blower fan runs ,disconnect fan connector at front of heater housing by fan motor.
The control module is in the top of the heater unit, towards firewall from top A/c line. , two wire loom plugs and 3 screws.The unit is inside the housing so the heat sink is coled by the airflow.
Only way I founf my prob was by fan randomly starting up with ign off when I was in the garage.WTF
Team Owner
Joined: Jan 2003
Posts: 20,316
Likes: 246
From: Summerland B.C. Canada
Originally Posted by rodj
two things
You will always hear the A/c clutch click in when you reconnect the battery.Can be killed by pressing off on A/c panel
Most likely fan blower control module has gone.This gets power direct from the battery , so can start fan at random if faulty.
Connect battery , if blower fan runs ,disconnect fan connector at front of heater housing by fan motor.
The control module is in the top of the heater unit, towards firewall from top A/c line. , two wire loom plugs and 3 screws.The unit is inside the housing so the heat sink is coled by the airflow.
Only way I founf my prob was by fan randomly starting up with ign off when I was in the garage.WTF
You will always hear the A/c clutch click in when you reconnect the battery.Can be killed by pressing off on A/c panel
Most likely fan blower control module has gone.This gets power direct from the battery , so can start fan at random if faulty.
Connect battery , if blower fan runs ,disconnect fan connector at front of heater housing by fan motor.
The control module is in the top of the heater unit, towards firewall from top A/c line. , two wire loom plugs and 3 screws.The unit is inside the housing so the heat sink is coled by the airflow.
Only way I founf my prob was by fan randomly starting up with ign off when I was in the garage.WTF
http://members.shaw.ca/dankai/AC%20Electronic.pdf
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
Cruise-In IV Veteran
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When you disconnect the battery, the ECM switches the A/C on automatically by default the first time the engine is started.
That still doesn't explain why the climate control button doesn't turn it OFF, though....
That still doesn't explain why the climate control button doesn't turn it OFF, though....
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
I think it was posted - Power to the Blower Module is hot at all times, on this Year, via a fusible link behind the Battery. Module has an internal short or other electronic fault, you get continuous battery power to the Blower. The only other cause of this symptom is when the 5 amp fuse on the Blower Voltage return line opens. For whatever reason, that can trick the Module into providing continous voltage to the Blower, even with the key off. I'd check the fuse - it's on the Firewall to the left of the Evaporator Case. If good, it needs a new Module.