'AUTO' light flashing on climate control
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Heel & Toe
Joined: Sep 2002
Posts: 15
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From: NB
'AUTO' light flashing on climate control
When I start my 1990 convertable (automatic) the 'AUTO' light flashes on the climate control display (if 'AUTO' was used prior to shutting off). If 'OFF' was last used, then the 'OFF' light flashes when the car is started. These lights seem to flash for several minutes & then stop. The AC also seems to be working/not working off & on. Any suggestions as to what is happening?
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Re: 'AUTO' light flashing on climate control (FSTRNU)
My does it because I have shorted sensors
Burning Brakes
Joined: Feb 2000
Posts: 824
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From: Camden SC
Re: 'AUTO' light flashing on climate control (FSTRNU)
Your likely setting a C68 (Electronic Climate Control) code. If you have the factroy service manual, head for page 1C1-2. The next 10 pages are the trouble shooting tips. The unit will flash the mode it is in when it detects a problem. Basically, hold the fan up and down buttons in at the same time for 5 seconds, release. It will display OO through 10. Believe they are listed in the tech sections. Let us know.
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Drifting
Joined: May 2001
Posts: 1,726
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From: COCOA Florida
Re: 'AUTO' light flashing on climate control (d5dpdm)
Follow this diagnostic procedure first
It means that there is a code set in the memory due to some momentary or permanent fault that was seen during operation. if you need directions on reading the data
diagnosis
if a system fault is detected, the LED indicator above the mode button depressed on the control head will flash for one minute. Diagnostic Trouble Codes (DTC's) will then be stored. DTCs are only stored when a system fault is present. History DTC's cannot be set except for DTC 09 (LOW FREON)
To enter the diagnostic mode, push and hold the fan "up" and fan "down" arrows at the same time for about 5 seconds.
The LCD wil show "-00.", push "AUTO FAN" and the LCD will show any fault DTC's stored in the programmer
Description DTCs
none 00
temperature door motor circuit fault 01
temperature door motor circuit fault 02
outside air temp sensor open 03
outside air temp sensor short 04
inside air temp sensor open 05
inside air temp sensor short 06
sun load sensor open 07
low refrigerant detected 09
Serial data failure 10
you can check some other stuff while in the diagnostic mode like system parameters, circuits or systems. to do this, press the fan "up" or fan "down" button. once the parameter to be checked has been chosen, the fan "AUTO" BUTTON is pressed and a diagnostic value is displayed on the LCD. once you are done, move to any other mode to exit the diagnostics.
sounds like you have a common problem. did you loose the refrigerant charge. you know you need to disconnect the battery for about 10 minutes to clear the memory codes for code 09, loss of refrigerant.
since you are getting the BLINKING lights, some codes are being set...either really or due to a non operational fault...like grounds, loose plugs, connections etc.
It means that there is a code set in the memory due to some momentary or permanent fault that was seen during operation. if you need directions on reading the data
diagnosis
if a system fault is detected, the LED indicator above the mode button depressed on the control head will flash for one minute. Diagnostic Trouble Codes (DTC's) will then be stored. DTCs are only stored when a system fault is present. History DTC's cannot be set except for DTC 09 (LOW FREON)
To enter the diagnostic mode, push and hold the fan "up" and fan "down" arrows at the same time for about 5 seconds.
The LCD wil show "-00.", push "AUTO FAN" and the LCD will show any fault DTC's stored in the programmer
Description DTCs
none 00
temperature door motor circuit fault 01
temperature door motor circuit fault 02
outside air temp sensor open 03
outside air temp sensor short 04
inside air temp sensor open 05
inside air temp sensor short 06
sun load sensor open 07
low refrigerant detected 09
Serial data failure 10
you can check some other stuff while in the diagnostic mode like system parameters, circuits or systems. to do this, press the fan "up" or fan "down" button. once the parameter to be checked has been chosen, the fan "AUTO" BUTTON is pressed and a diagnostic value is displayed on the LCD. once you are done, move to any other mode to exit the diagnostics.
sounds like you have a common problem. did you loose the refrigerant charge. you know you need to disconnect the battery for about 10 minutes to clear the memory codes for code 09, loss of refrigerant.
since you are getting the BLINKING lights, some codes are being set...either really or due to a non operational fault...like grounds, loose plugs, connections etc.
Instructor
Joined: Jul 2011
Posts: 116
Likes: 0
From: Hastings Florida
I don't know if my particular problem with the electronic climate control relates with this (as far as "flashing" goes), but the indicator window where you see the temp readouts on mine doesn't exactly "flash" ... it just kind of goes nuts. It makes me think that connections have weathered somewhat which would call for a good cleaning.
But, this isn't a consistent problem as it seems to only act up when there's a lot of moisture in the air. Then, it tends to clear up on its own as the day goes on. (humidity/temperature changes?).
This was even happening when the a/c system itself was out of commision due to a freon leak at the schrader valve. (Having that taken care of got the ac working again) .. but the odd display behavior continued. Even to the point where trying to change settings weren't being responsive on the control face ... but like I said, it's not consistent and often clears up on its own after a while, but it's a nuseance.
To sum up: I'm thinking just clean up the contacts and find a way to weatherproof the controller so moisture can't build up in it.
I hadn't thought that the controller itself could store codes in it .. so I'll run a diagnostic on that to find out. I needed that tip. Thanks.
But, this isn't a consistent problem as it seems to only act up when there's a lot of moisture in the air. Then, it tends to clear up on its own as the day goes on. (humidity/temperature changes?).
This was even happening when the a/c system itself was out of commision due to a freon leak at the schrader valve. (Having that taken care of got the ac working again) .. but the odd display behavior continued. Even to the point where trying to change settings weren't being responsive on the control face ... but like I said, it's not consistent and often clears up on its own after a while, but it's a nuseance.
To sum up: I'm thinking just clean up the contacts and find a way to weatherproof the controller so moisture can't build up in it.
I hadn't thought that the controller itself could store codes in it .. so I'll run a diagnostic on that to find out. I needed that tip. Thanks.
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
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