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Old 09-30-2017, 10:04 PM   #1
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Hi guys, New to the forum so i hope i do this correctly. I have a 2009 GMC sierra 1500 4x extended cab with lt trim and 5.3l engine. my batt died and i jumped it my batt charger wasnt putting enough out. i got it started but now my ac blows hot air. the fuses appear to be ok, the compressor cycles I just cant get no cold air. What did i fry ????
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Old 10-01-2017, 01:40 PM   #2
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If you turn the A/C off, and run like in econ mode, can you change the output temp, by going to the extreme ends?

If no, you have a temp door actuator problem.....
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Old 10-01-2017, 03:39 PM   #3
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If you turn the A/C off, and run like in econ mode, can you change the output temp, by going to the extreme ends?

If no, you have a temp door actuator problem.....

i turned a/c off. Ran temp down to 60 but still had hot air. Think I fried the door actuators ? Maybe ? I would have thought the fuse wold protect the system. Maybe not
will door actuator show on scan/ code reader ???

thanks
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Old 10-02-2017, 10:31 PM   #4
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I doubt you fried it.......Actuators are known to fail, usually with gear stripping......you have to find the actuator....remove it and see if you can manually move the door, just to make sure it is not binding, obstructed or if the linkage is broken(that'* the worst case scenario)....

Cheap code reader/scan tool will not show data or codes......need an expensive bidirectional scan tool, like a Tech II, to read B(body) and U(communication) codes...also to read data, commanded position, and feedback from the actuator....

One question is, is this a split system where there are two actuators, one for each side, with a temp control for each side?
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Old 10-02-2017, 10:59 PM   #5
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I doubt you fried it.......Actuators are known to fail, usually with gear stripping......you have to find the actuator....remove it and see if you can manually move the door, just to make sure it is not binding, obstructed or if the linkage is broken(that'* the worst case scenario)....

Cheap code reader/scan tool will not show data or codes......need an expensive bidirectional scan tool, like a Tech II, to read B(body) and U(communication) codes...also to read data, commanded position, and feedback from the actuator....

One question is, is this a split system where there are two actuators, one for each side, with a temp control for each side?
it is the split system. The thing worked fine until I did the stupid jump. So frustrating
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Old 10-05-2017, 03:51 PM   #6
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At times when jump starting a vehicle you can logic lock any module that the vehicle is equipped with. Try removing power from the HVAC(heating ventilation and AC) module for 20 minutes and evaluate. Or disconnect the battery for 20 minutes, or touch the battery cables together for 20 seconds, and retest. This will reset the vehicles modules and will also force the HVAC control module to relearn all its actuators positions.
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Old 10-10-2017, 10:17 PM   #7
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Originally Posted by Tech II View Post
I doubt you fried it.......Actuators are known to fail, usually with gear stripping......you have to find the actuator....remove it and see if you can manually move the door, just to make sure it is not binding, obstructed or if the linkage is broken(that'* the worst case scenario)....

Cheap code reader/scan tool will not show data or codes......need an expensive bidirectional scan tool, like a Tech II, to read B(body) and U(communication) codes...also to read data, commanded position, and feedback from the actuator....

One question is, is this a split system where there are two actuators, one for each side, with a temp control for each side?
yes split system. I left batt disconnected for a couple of days. hooked everything up started truck and everything worked fine, cold air out both sides. went to adjust temps, now left side blows hot and i have cold on the right ? aaaarrrrgh.
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Old 10-10-2017, 10:18 PM   #8
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At times when jump starting a vehicle you can logic lock any module that the vehicle is equipped with. Try removing power from the HVAC(heating ventilation and AC) module for 20 minutes and evaluate. Or disconnect the battery for 20 minutes, or touch the battery cables together for 20 seconds, and retest. This will reset the vehicles modules and will also force the HVAC control module to relearn all its actuators positions.
worked part way. but with batt disconn for 2 days I still had memory on the radio then the left side went back to hot air with temp selected to 68 degs. try again ?
thanks for the help
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Old 10-16-2017, 11:28 AM   #9
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Have you checked for any codes setting? Being that is briefly functioned and then stopped it seems you may have a "dead spot" in the actuator potentiometer. I am with techII on this one. Most likely cause is an actuator concern. See if there is codes setting.
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