C4 Corvette Climate Control
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From: essex
C4 Corvette Climate Control
Some one on here may be able to help me with this problem
the light something flashes above the off button. But there are no codes displayed on the control readout the a/c was recharged in Nov 14 still working but does not seem to blow out as cold as it did
the light something flashes above the off button. But there are no codes displayed on the control readout the a/c was recharged in Nov 14 still working but does not seem to blow out as cold as it did
Team Owner
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You've put the control in the DIAGNOSTICS MODE? You didn't mention year and it may not be relevant but could certainly help. Do you get perhaps a SOLID BAR?
Last edited by WVZR-1; May 8, 2016 at 08:46 AM.
Team Owner
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I added a comment in my earlier post about a solid bar. Do you get the solid bar? What year? Can you use the AC CONTROL to access the other parameters that are available?
Team Owner
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Is the system still R12? You mention a performance issue so I'd think you have that checked. Why no codes displayed? No idea BUT perhaps if you remove power to the system the C68 panel will RESET and then display codes. The best confirmed RESET would of course be removing a battery cable and reset ALL.
I didn't look at an FSM to see which fuse might reset it but if you have one that might be the next logical move. The "solid bar" is a possibility with a later C4 C68 panel and NOT a '90.
I didn't look at an FSM to see which fuse might reset it but if you have one that might be the next logical move. The "solid bar" is a possibility with a later C4 C68 panel and NOT a '90.
Last edited by WVZR-1; May 8, 2016 at 09:26 AM.
Race Director
Joined: Apr 2002
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From: Anaheim CA
On '89 and earlier cars you can remove the CTSY/CLK fuse. I don't know what that fuse is called in 1990 and later cars. It removes power from the memory in the HVAC controller and it has to recalibrate and relearn. Note that the temperature setting will default to 75°, which is a good way to verify that the reset worked.
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Joined: Mar 2015
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From: essex
I removed the CTSY/CLK fuse it showed -- for about 15/20 sec is this normal after reset (removing the CTSY/CLK fuse)
and now it has recalibrate and relearn the temperature is show 75°, as you said which is a good way to verify that the reset worked but the light is still flashing I am going to get them to check the system for me today thanks everyone for there help and advise
and now it has recalibrate and relearn the temperature is show 75°, as you said which is a good way to verify that the reset worked but the light is still flashing I am going to get them to check the system for me today thanks everyone for there help and advise
Last edited by Gary Bagley; May 9, 2016 at 03:36 AM.
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From: Pittsburgh PA
Gray
I watched your video of FB and notice that everything appears to function normally and only after pressing the 'Off' button do you get the flashing light. According to the Electrical Diagnosis Service Manual it states the following.
"If the Heating and A/C System detects a fault in one of the system components, it will be indicated by a flashing MODE Indicator when the Ignition Switch is first turned "ON."
So if this light only starts flashes after you run though the function this would be the reason you are not getting any codes and that it is something else. I would consider taking the control head apart and cleaning the contacts as show in the video I posted.
Ken
I watched your video of FB and notice that everything appears to function normally and only after pressing the 'Off' button do you get the flashing light. According to the Electrical Diagnosis Service Manual it states the following.
"If the Heating and A/C System detects a fault in one of the system components, it will be indicated by a flashing MODE Indicator when the Ignition Switch is first turned "ON."
So if this light only starts flashes after you run though the function this would be the reason you are not getting any codes and that it is something else. I would consider taking the control head apart and cleaning the contacts as show in the video I posted.
Ken
Last edited by kenpeindl; May 9, 2016 at 07:51 AM.
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OP - Do you have the FSM for the car? Is the car R12? Maybe not relevant but could be. You mention performance seems less than desired maybe.
I believe that since the C68 panel relies on information supplied to the programmer from the CCM and the external sensors you maybe just do the "first evaluation" check mentioned in the FSM. I don't believe I'd go first to dis-assembly of anything.
If the there's a system situation I'd think at some point the "results" would be something other than the "expected results" the procedure mentions.
The "first evaluation check" is covered in the 8A-62
I would tear apart "NOTHING" first!
Your location I'd think would dictates that you have the FSM available.
I believe that since the C68 panel relies on information supplied to the programmer from the CCM and the external sensors you maybe just do the "first evaluation" check mentioned in the FSM. I don't believe I'd go first to dis-assembly of anything.
If the there's a system situation I'd think at some point the "results" would be something other than the "expected results" the procedure mentions.
The "first evaluation check" is covered in the 8A-62
I would tear apart "NOTHING" first!
Your location I'd think would dictates that you have the FSM available.
Last edited by WVZR-1; May 9, 2016 at 09:07 AM.