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...each and every time I exit (and turn off the car for the day) I make sure to turn off everything, radio, any HVAC stuff that I may have had on, etc. But now, sometimes when I start my car, I notice that rather quickly I start to hear the blower/fan is on, and when I look at the controls, the "lights" in the A/C power switch and also the one which means you are allowing air to come in from the outside, this buttons' light is also on...
Perhaps it would have been better that you had started a separate thread to avoid confusion
What you are describing seems to be the same behavior that occurs the first time the car is started after having its battery disconnected. Could it be that your battery is on its way out and when starting the car its voltage is dropping below a certain threshold, causing this behavior? You mentioned above in another post something about your battery being drained...
When starting the car and having the A/C problem, have you noticed if the DIC is defaulting to odometer even if you left it displaying any other info when you turned off the car?
It might be a good idea to have your battery load-tested at an auto parts store.
Perhaps it would have been better that you had started a separate thread to avoid confusion
What you are describing seems to be the same behavior that occurs the first time the car is started after having its battery disconnected. Could it be that your battery is on its way out and when starting the car its voltage is dropping below a certain threshold, causing this behavior? You mentioned above in another post something about your battery being drained...
When starting the car and having the A/C problem, have you noticed if the DIC is defaulting to odometer even if you left it displaying any other info when you turned off the car?
It might be a good idea to have your battery load-tested at an auto parts store.
Was thinking the same thing .I did replace the battery,
GCG,
Thanks. Should I be testing for voltage or just continuity?
Continuity between pin L from the StarConnector 1 and the corresponding pin in the HVAC Control Module's connector, after opening the StarConnector 1 (refer to schematic and additional details in Post 17 above).
I would suggest to start by addressing the lack of communications with the HVAC Control Module. All these communications take place through the Serial Data Bus. The Star Connectors, located by the passenger's foot well, are very helpful when troubleshooting the bus.
If this is the only "No Comm" code you have, then you can troubleshoot it by opening the Star Connector 1 and then proceed to verify continuity between pin L from the Star Connector 1 and the corresponding pin in the HVAC Control Module's connector.
If the wire tests OK, double check the serial wire female pin in the HVAC connector to make sure it is not deformed and has a good grip. If not, you would need to repair it to eliminate bad contacts.
Take a look at the following schematic showing the link between pin L from the Star Connector 1 and the HVAC Control Assembly.
You're not going to get the ac issues resolved until you fix the no comm condition.
so how do we know the interior temperature sensor is working?
Now that summer is here I'm back at the A/C not working. I was letting the car run in my garage to warm up so I could change out an 02 sensor. It was around 90 degrees in the garage when my A/C turned on by it self. I could operate all the functions of the A/C even turn it off on back on. shut the engine off and changed the 02 sensor. half hour later stared the engine let it run for a while but no A/C light came on nothing it was dead to me. any thoughts?
Yes I have had a similar issue with my 2000 double din hvac control. When I got the car the blower would not come on, then one day it worked for no apparent reason, then it quit working again.
I took the dash apart to change the IPC and Good ole Bill suggested I remove the hvac control and hit the lose solder Joints. I wasn't having a light problem
but I did it anyway. AC works as it should now. There is also a relay in the foot well next to the BCM that you should hear click when the blower is switched on
Yes I have had a similar issue with my 2000 double din hvac control. When I got the car the blower would not come on, then one day it worked for no apparent reason, then it quit working again.
I took the dash apart to change the IPC and Good ole Bill suggested I remove the hvac control and hit the lose solder Joints. I wasn't having a light problem
but I did it anyway. AC works as it should now. There is also a relay in the foot well next to the BCM that you should hear click when the blower is switched on
This was my thoughts the first I saw this thread but I saw it was a year old so I wasn't going to reply. I looked to see if anybody else mentioned this and only today did it get pointed out. If you have dual zone climate control this is something everybody should do.
Originally Posted by dleibman
Why is there so many problems with the vette HVAC units. Had some also then it healed itself the second time around in a year
Because GM put some fairly large surface mount components on the HVAC controller board and when they heat cycle and expand and contract, eventually the welds come loose on the components. At that point you have to get a soldering iron out and add solder to them. The original process is actually an ultrasonic weld but they're not quite as robust as actually flowing solder.
06-08-2018, 04:25 PM
