ac problems- no mode control-calling C4C5 specialist
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Joined: Jun 2002
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From: gowen mi
ac problems- no mode control-calling C4C5 specialist
i've got the dual zone auto a/c control- no matter whether its in manual or auto mode or where i set the mode for air delivery, the air comes out some dash vents and some lower vents- will not go to defrost or any songle mode. in auto it does switch from recirc to outside air as temp inside goes down and also regulates the blower speed according to temp setting-just no control of direction of air flow. any ideas?? no codes and fuses are all ok. tried to reset by pulling fuses so it would cycle actuators but no difference. maybe vac leak? where is vac source? how do i get to where the vac connects to control to see if i have supply? thanks for any help! :confused: :confused: :confused:
Drifting
Joined: Dec 2000
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From: Shelton CT
Cruise-In II Veteran
Re: ac problems- no mode control-calling C4C5 specialist (nassau99)
Hi there,
Your vacuum source is located at the rear of the intake manifold, and runs to a vacuum junction, located below the battery tray.
Has there been some intake work done recently????
Have you ever had a leaking battery????
Please let us know, and we can continue, c4c5 :chevy
Your vacuum source is located at the rear of the intake manifold, and runs to a vacuum junction, located below the battery tray.
Has there been some intake work done recently????
Have you ever had a leaking battery????
Please let us know, and we can continue, c4c5 :chevy
Thread Starter
Instructor
Joined: Jun 2002
Posts: 136
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From: gowen mi
Re: ac problems- no mode control-calling C4C5 specialist (c4c5specialist)
thanks for responding- never had any intake work as far as i know, but i just bought it so its possible,but doesn't appear to be. the batterry has been replaced, but no indication of acid-previous owner said he left it in last winter and would not take charge this spring when he took out of storage, so he replaced it. any thoughts on where to go from here? is the most likely thing a vac problem with what i described? i've tried to see behind the intake for the vac line but not sure what i'm looking for and kind of tight back there. how do i access the other end to see if we have vac to control?
thanks
thanks
Drifting
Joined: Dec 2000
Posts: 1,516
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From: Shelton CT
Cruise-In II Veteran
Re: ac problems- no mode control-calling C4C5 specialist (nassau99)
Hi there,
You will need to remove the passenger inner fender, to access the area where the PCM is.
Toward the rear of this area, you will see a plastic hose, attached to a plastic can, near the hinges for the door.
Look there for any damage.
Besttoyou, c4c5 :chevy
You will need to remove the passenger inner fender, to access the area where the PCM is.
Toward the rear of this area, you will see a plastic hose, attached to a plastic can, near the hinges for the door.
Look there for any damage.
Besttoyou, c4c5 :chevy
Thread Starter
Instructor
Joined: Jun 2002
Posts: 136
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From: gowen mi
Re: ac problems- no mode control-calling C4C5 specialist (c4c5specialist)
well you were right again c4c5specialist! pulled the battery (that had been previously replaced) and found that the previous battery had leaked acid on the harnnes and caused the vacumn line to disintegrate. so obviously the cause to my woes. flushed and cleaned with baking soda solution and water, dried and sprayed with rustproofing. replaced battery with OPTIMA RED TOP. i would highly reccommend this to all c5 owners- dump the acid plate battery and go with optima to eliminate this problem forever!! would'nt this open line be just like a vaumn leak in the manifold? what does this do to the engine function? cause to idle rough, misfire, run lean/rich or does computer somehow compensate for a vacumn leak??? thanks for your help! :cheers:
Drifting
Joined: Dec 2000
Posts: 1,516
Likes: 0
From: Shelton CT
Cruise-In II Veteran
Re: ac problems- no mode control-calling C4C5 specialist (nassau99)
Hi there,
Yes, if could cause a slightly rough idle, slight hesitation, however, it would be a slight vacuum leakage, so at times you might not even notice a difference.
Glad it all worked out for you, c4c5 :chevy
Yes, if could cause a slightly rough idle, slight hesitation, however, it would be a slight vacuum leakage, so at times you might not even notice a difference.
Glad it all worked out for you, c4c5 :chevy
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