??? - 90 corvette - electronic A/C control - blinking indicator light
Thread Starter
Race Director
Joined: Aug 2000
Posts: 11,470
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??? - 90 corvette - electronic A/C control - blinking indicator light
my 90 is equipped with the C68, electronic air conditioning control option. yesterday, I went out for a short drive, and noticed the small green indicator light, on the center console, heater/AC control panel, "blinking," whether it was either "off" or in the "auto" position. after about a minute or so, the blinking indicator went steady state, which I'm guessing is normal. I have never experienced this on any other C4 I've owned. yesterday was the first time I noticed this - normal or what - ??? - or, is it just a matter on having never noticed this before? can't seem to find anything in the owners manual. TIA....
Team Owner
Joined: Sep 2003
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my 90 is equipped with the C68, electronic air conditioning control option. yesterday, I went out for a short drive, and noticed the small green indicator light, on the center console, heater/AC control panel, "blinking," whether it was either "off" or in the "auto" position. after about a minute or so, the blinking indicator went steady state, which I'm guessing is normal. I have never experienced this on any other C4 I've owned. yesterday was the first time I noticed this - normal or what - ??? - or, is it just a matter on having never noticed this before? can't seem to find anything in the owners manual. TIA....
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The C68 system will cause that indicator light to flash for about a minute if the system diagnostics finds a problem. Specific error codes are then stored in memory.
This is from my '92 FSM but the code retrieval should be the same for the 90.
To go into diagnostic mode, push the fan Up and Down arrows at the same time for about 5 seconds.
The display should show "-00" Push the Auto Fan button and any error codes will be displayed:
01 Temp Door Motor Circuit Fault
02 Same as 01 (for pass side)
03 Ambient Sensor Open
04 Ambient Sensor Short
05 In-Vehicle Temp Sensor Open
06 In-Vehicle Temp Sensor Short
07 Solar Load Sensor Open
08 Solar Load Sensor Short
09 Low Freon Detected
10 UART Failure
I think that Code 09 will be the likely suspect. This indicates that the refrigerant on the low pressure side is too low for operation. Get the system pressures checked and re-fill as necessary.
This is from my '92 FSM but the code retrieval should be the same for the 90.
To go into diagnostic mode, push the fan Up and Down arrows at the same time for about 5 seconds.
The display should show "-00" Push the Auto Fan button and any error codes will be displayed:
01 Temp Door Motor Circuit Fault
02 Same as 01 (for pass side)
03 Ambient Sensor Open
04 Ambient Sensor Short
05 In-Vehicle Temp Sensor Open
06 In-Vehicle Temp Sensor Short
07 Solar Load Sensor Open
08 Solar Load Sensor Short
09 Low Freon Detected
10 UART Failure
I think that Code 09 will be the likely suspect. This indicates that the refrigerant on the low pressure side is too low for operation. Get the system pressures checked and re-fill as necessary.
Race Director
Joined: Oct 2011
Posts: 16,092
Likes: 819
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
The C68 system will cause that indicator light to flash for about a minute if the system diagnostics finds a problem. Specific error codes are then stored in memory.
This is from my '92 FSM but the code retrieval should be the same for the 90.
To go into diagnostic mode, push the fan Up and Down arrows at the same time for about 5 seconds.
The display should show "-00" Push the Auto Fan button and any error codes will be displayed:
01 Temp Door Motor Circuit Fault
02 Same as 01 (for pass side)
03 Ambient Sensor Open
04 Ambient Sensor Short
05 In-Vehicle Temp Sensor Open
06 In-Vehicle Temp Sensor Short
07 Solar Load Sensor Open
08 Solar Load Sensor Short
09 Low Freon Detected
10 UART Failure
I think that Code 09 will be the likely suspect. This indicates that the refrigerant on the low pressure side is too low for operation. Get the system pressures checked and re-fill as necessary.
This is from my '92 FSM but the code retrieval should be the same for the 90.
To go into diagnostic mode, push the fan Up and Down arrows at the same time for about 5 seconds.
The display should show "-00" Push the Auto Fan button and any error codes will be displayed:
01 Temp Door Motor Circuit Fault
02 Same as 01 (for pass side)
03 Ambient Sensor Open
04 Ambient Sensor Short
05 In-Vehicle Temp Sensor Open
06 In-Vehicle Temp Sensor Short
07 Solar Load Sensor Open
08 Solar Load Sensor Short
09 Low Freon Detected
10 UART Failure
I think that Code 09 will be the likely suspect. This indicates that the refrigerant on the low pressure side is too low for operation. Get the system pressures checked and re-fill as necessary.
Thread Starter
Race Director
Joined: Aug 2000
Posts: 11,470
Likes: 764
The C68 system will cause that indicator light to flash for about a minute if the system diagnostics finds a problem. Specific error codes are then stored in memory.
This is from my '92 FSM but the code retrieval should be the same for the 90.
To go into diagnostic mode, push the fan Up and Down arrows at the same time for about 5 seconds.
The display should show "-00" Push the Auto Fan button and any error codes will be displayed:
01 Temp Door Motor Circuit Fault
02 Same as 01 (for pass side)
03 Ambient Sensor Open
04 Ambient Sensor Short
05 In-Vehicle Temp Sensor Open
06 In-Vehicle Temp Sensor Short
07 Solar Load Sensor Open
08 Solar Load Sensor Short
09 Low Freon Detected
10 UART Failure
I think that Code 09 will be the likely suspect. This indicates that the refrigerant on the low pressure side is too low for operation. Get the system pressures checked and re-fill as necessary.
This is from my '92 FSM but the code retrieval should be the same for the 90.
To go into diagnostic mode, push the fan Up and Down arrows at the same time for about 5 seconds.
The display should show "-00" Push the Auto Fan button and any error codes will be displayed:
01 Temp Door Motor Circuit Fault
02 Same as 01 (for pass side)
03 Ambient Sensor Open
04 Ambient Sensor Short
05 In-Vehicle Temp Sensor Open
06 In-Vehicle Temp Sensor Short
07 Solar Load Sensor Open
08 Solar Load Sensor Short
09 Low Freon Detected
10 UART Failure
I think that Code 09 will be the likely suspect. This indicates that the refrigerant on the low pressure side is too low for operation. Get the system pressures checked and re-fill as necessary.
EDIT:
Last edited by Joe C; Feb 28, 2015 at 03:44 PM.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Disconnecting the battery will clear the C68 codes but that system does not store any history codes. If the code you had was an 09 for low pressure side loss of refrigerant, and you don't bring the low side pressure back up, the error code will come back at some point.
Drifting
Joined: Jul 2009
Posts: 1,258
Likes: 98
From: Ashland PA
2021 C4 of the Year - Modified Finalist
Disconnecting the battery will clear the C68 codes but that system does not store any history codes. If the code you had was an 09 for low pressure side loss of refrigerant, and you don't bring the low side pressure back up, the error code will come back at some point.
I had the code 9 last spring this is wen I looked it up in the FSM, I got lucky and the reset worked.
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Thread Starter
Race Director
Joined: Aug 2000
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In the 90 FSM the first thing it says in the troubleshooting tree for low freon is to disconnect the fuses or battery, reconnect after 15 seconds, run engine 5 minutes at 1000 rpm, if code 9 resets then it goes on from there. if code 9 does not reset the reset system OK.
I had the code 9 last spring this is wen I looked it up in the FSM, I got lucky and the reset worked.
I had the code 9 last spring this is wen I looked it up in the FSM, I got lucky and the reset worked.