Climate Control 'Off' Light
Thread Starter
Drifting
Joined: Aug 2009
Posts: 1,971
Likes: 243
Climate Control 'Off' Light
my 1994
When my climate control system is 'off' sometimes the light is lit but more often the light is not lit. The climate control unit itself seems to work without a hitch. Is this as simple as a loose wire or bad solder joint? Or is it actually even normal? Just to be clear, the light is not flashing indicating a problem, just sometimes when the system is turned off it is lit and sometimes it is not. Does it have anything to do with the healights being on or off? Or that daylight sensing sensor in the dash?
Do the 94s have the automatic headlights that turn on when it gets dark out? I thought that is what that dash sensor is for but my lights don't turn on unless I use the headlight switch. So either it doest have that feature, its been disabled, or its broken. I guess what I am asking is what is the purpose of that sensor?
When my climate control system is 'off' sometimes the light is lit but more often the light is not lit. The climate control unit itself seems to work without a hitch. Is this as simple as a loose wire or bad solder joint? Or is it actually even normal? Just to be clear, the light is not flashing indicating a problem, just sometimes when the system is turned off it is lit and sometimes it is not. Does it have anything to do with the healights being on or off? Or that daylight sensing sensor in the dash?
Do the 94s have the automatic headlights that turn on when it gets dark out? I thought that is what that dash sensor is for but my lights don't turn on unless I use the headlight switch. So either it doest have that feature, its been disabled, or its broken. I guess what I am asking is what is the purpose of that sensor?
Team Owner
Joined: Jan 2009
Posts: 73,568
Likes: 33
From: Somewhere in Mo
St. Jude Donor '09-'10, '14
Borrowed from member perfusion from another thread. It sounds to me like your contacts are going bad.
It's an easy fix.
The sensor on your dash is for the climate control IIRC
It's an easy fix.
Yep... Common problem. He needs to take the Climate Control (CC) unit out and clean the circuit board. Before you (or he) get scared at the sound of this, let me just tell you that it is EASY.
Start by removing the lid to the center console (4 bolts). Next, lift up the carpet liner inside. At the rear of the shifter trim plate, there will be 2 bolts that hold the back down. A third is under the cupholder/ashtray linter. With those three out, the shifter trim plate should easily lift up and away. Just position it to the side and remove the two (identical to the previous 3) bolts at the bottom of the radio/CC trim plate. Next, remove the central A/C vent (2 Torx screws). When that's done, you'll see a third Torx screw that's holding the top of the radio/CC trim piece in that needs to be revomed. After that trim piece is off, you'll notice the two bolts holding the CC unit in place - remove them. The unit will now slide straight out, and you can unplug it from the wiring harness in the rear.
Take the CC unit inside to work on it. There will be 6 *small* bolts that need to come out - 4mm or 4.5mm, if I remember correctly. One tip I can give you is this - when you've got all 6 removed (two on the back surface, and 4 around the perimeter), point the face of the CC unit towards the ground while separating the two halves - you don't want the individual buttons to fall all over the place. With that complete, you will be able to remove the internals. There will be 2 circuit boards joined like a "T". They simply pull apart. Set the larger of the two aside. Then CAREFULLY remove the 4 lightbulbs (will look like grey plastic plugs from the back) with a flathead screwdriver - they should take about a 1/4 turn counterclockwise to "unlock." After they're out, flip the board over and proceed with the cleaning.
All I do is *lightly* go over the contact points (you'll be able to tell what I'm talking about when you have it apart) with a soft pencil eraser, and then give it a good wipe with some Isopropyl Alcohol pads. After it's dry, I re-assemble and head back to the car. Plug it in to the wiring harness for a test - it should work as new!
Re-assemble all other trim pieces, etc. in the order they were removed. Shouldn't take more than an hour...maybe a tick more depending on how careful you are. It really *IS* an easy job, though, so take your time and all will be fine.
Hope this helps! I've done it twice on my 96 with no problems (most recently over this past weekend). It sure beats a new unit at dealer prices (around $375, I think)!!!!!
Start by removing the lid to the center console (4 bolts). Next, lift up the carpet liner inside. At the rear of the shifter trim plate, there will be 2 bolts that hold the back down. A third is under the cupholder/ashtray linter. With those three out, the shifter trim plate should easily lift up and away. Just position it to the side and remove the two (identical to the previous 3) bolts at the bottom of the radio/CC trim plate. Next, remove the central A/C vent (2 Torx screws). When that's done, you'll see a third Torx screw that's holding the top of the radio/CC trim piece in that needs to be revomed. After that trim piece is off, you'll notice the two bolts holding the CC unit in place - remove them. The unit will now slide straight out, and you can unplug it from the wiring harness in the rear.
Take the CC unit inside to work on it. There will be 6 *small* bolts that need to come out - 4mm or 4.5mm, if I remember correctly. One tip I can give you is this - when you've got all 6 removed (two on the back surface, and 4 around the perimeter), point the face of the CC unit towards the ground while separating the two halves - you don't want the individual buttons to fall all over the place. With that complete, you will be able to remove the internals. There will be 2 circuit boards joined like a "T". They simply pull apart. Set the larger of the two aside. Then CAREFULLY remove the 4 lightbulbs (will look like grey plastic plugs from the back) with a flathead screwdriver - they should take about a 1/4 turn counterclockwise to "unlock." After they're out, flip the board over and proceed with the cleaning.
All I do is *lightly* go over the contact points (you'll be able to tell what I'm talking about when you have it apart) with a soft pencil eraser, and then give it a good wipe with some Isopropyl Alcohol pads. After it's dry, I re-assemble and head back to the car. Plug it in to the wiring harness for a test - it should work as new!
Re-assemble all other trim pieces, etc. in the order they were removed. Shouldn't take more than an hour...maybe a tick more depending on how careful you are. It really *IS* an easy job, though, so take your time and all will be fine.
Hope this helps! I've done it twice on my 96 with no problems (most recently over this past weekend). It sure beats a new unit at dealer prices (around $375, I think)!!!!!
The sensor on your dash is for the climate control IIRC
Race Director
Joined: Oct 2005
Posts: 11,770
Likes: 175
From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
my 1994
When my climate control system is 'off' sometimes the light is lit but more often the light is not lit. The climate control unit itself seems to work without a hitch. Is this as simple as a loose wire or bad solder joint? Or is it actually even normal? Just to be clear, the light is not flashing indicating a problem, just sometimes when the system is turned off it is lit and sometimes it is not. Does it have anything to do with the healights being on or off? Or that daylight sensing sensor in the dash?
Do the 94s have the automatic headlights that turn on when it gets dark out? I thought that is what that dash sensor is for but my lights don't turn on unless I use the headlight switch. So either it doest have that feature, its been disabled, or its broken. I guess what I am asking is what is the purpose of that sensor?
When my climate control system is 'off' sometimes the light is lit but more often the light is not lit. The climate control unit itself seems to work without a hitch. Is this as simple as a loose wire or bad solder joint? Or is it actually even normal? Just to be clear, the light is not flashing indicating a problem, just sometimes when the system is turned off it is lit and sometimes it is not. Does it have anything to do with the healights being on or off? Or that daylight sensing sensor in the dash?
Do the 94s have the automatic headlights that turn on when it gets dark out? I thought that is what that dash sensor is for but my lights don't turn on unless I use the headlight switch. So either it doest have that feature, its been disabled, or its broken. I guess what I am asking is what is the purpose of that sensor?
Unless your C4 is an export model, it does not have automatic headlights. Some of the later year "export" C4's did, but I don't know exactly what year that started.
Now, for your first question about the "off" light being lit sometimes and others not.
If I am understanding your question correctly, it could be that the buttons are not making contact as they should.
See if the information in this thread helps.
http://forums.corvetteforum.com/c4-g...on-repair.html
Team Owner
Joined: Jan 2009
Posts: 73,568
Likes: 33
From: Somewhere in Mo
St. Jude Donor '09-'10, '14
