Jump to content

2009 Sierra 1500 HVAC only does full hot OR cold

MikeCanada

Recommended Posts

MikeCanada New Member

MikeCanada

Posted
Posted

Hey Guys,

 

First time poster. My 09 sierra 1500 has treated me great since i bought it. 240000km on it with only 1 broken leaf spring (recall) and a stuck fuel tank vent. My little broken annoyance happens to be in the HVAC system. I have the dual climate digital controls. Issue is, setting the temp manually, it will either blow full hot or full cold. Generally when set from 16-24 deg C it will blow the same level of cold (either ac full cold or if not engaged then just ambient temp cold) and 25-28(HI) it will blow full hot. Seems to be no moderation. All vents blowing same temp. id guess there is multiple blend doors (1 driver side, 1 passenger 1 master?). If i set driver side to full hot, and passenger to full cold they will blow accordingly but still no temp regulation. Any ideas?

swathdiver Senior Enthusiast

swathdiver

Posted
Posted

To know for sure Mike, you need a Tech-2 or something similar to read the BCM codes.  This will tell you which actuators are not working right and why.  There are 4 actuators and 3 different part numbers.  Could also be the controller.  I'm guessing but I think it could be the Mode actuator (89018374).  This one is behind the radio/nav, to the left of the center vents, installed vertically and facing left.  

 

Stick with factory parts, the folks here say the aftermarket ones don't last.    

MikeCanada New Member

MikeCanada

Posted
  • Author
Posted

Thanks for the quick reply. I should be able to get my hands on a tech 2 scanner this week. When I hook up the tech 2, will it show me an error code for the malfunctioning actuator? 

swathdiver Senior Enthusiast

swathdiver

Posted
Posted
3 hours ago, MikeCanada said:

Thanks for the quick reply. I should be able to get my hands on a tech 2 scanner this week. When I hook up the tech 2, will it show me an error code for the malfunctioning actuator? 

Yes, each actuator has its own trouble code and 3 symptoms as to why it failed.

 

B0228 - Recirculate (89018365)

B0413 - Driver's Side (89018375)

B0423 - Passenger Side (89018375)

B3779 - Mode (89018374)

 

Symptom 02 - Short to Ground

Symptom 05 - Short to Battery or Open

Symptom 61 - Actuator Stuck

 

When you get into the Special Functions setting under the HVAC controls, you can command the actuators to move (if they can), hotter or colder.  You can also perform a reset.  When they get 4 or 5 counts out of sequence between commanded and actual the code sets.  

 

Started out with one bad one on my truck, then eventually all but one throws a code once in a while.  We use the Tech-2 to force them into position but now that they all need it, I might as well stop kicking the can down the road and order them up.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • Grumpy Bear
      Grumpy Bears 2015 Silverado 2WD

      By Grumpy Bear · Posted

      Notes 7/18/2026   3,400 miles on this batch of Mobil 1 Euro 5W40 since the GDI pump replacement. Alcohol runs very clean when ring seal is tight and the sump isn't getting hosed with fuel. Checked oil level at fill up today as is my practice and grabbed a white Kleenex to look at the color. What color?  I was going to change it but.....  
    • Another JR
      2 speed transfer case optional now?

      By Another JR · Posted

      4 low is really nice on steep boat ramps. 
    • Chuck FB
      Gas Prices

      By Chuck FB · Posted

      Interesting, I suspect I would have fueled up in Lee Vining as the day prior I would have filled up either in Laughlin or near there and maybe again before I entered Death Valley and once out the other side late that evening as I kept on driving into the night up near Lee Vining. Next morning I most likely fueled up in LV before heading over Tioga Pass into ( as I refer to it as "Yose .... Mite" 😁 ). And again that was 19 years ago but the price then must not have jumped out at me like the 5 bill a gallon theme of nutty cult hippy country Big Sir or head so far up their rear Aspen. I'd be curious to know where the highest prices are in the lower 48, I probably would not be far off to guess somewhere in Cali forn ie. Coldfoot and Prudhoe bay may have those prices beat but that is a whole other world up there and when prices are more normal elsewhere that is about what they can be up there I believe in no mans land. Anyway interesting that the 395 corridor is hosing people and the thing is, its tourist season and its not like there are a lot of competition options when driving up that highway from what I could see. Yup, big ole Boaterhomes and various other RV's ahead and behind me at the Yosemite entrance gate and they have to get their fuel somewhere.  
    • Atlas
      Gas Prices

      By Atlas · Posted

      Those can be high, as well as the big California cities. The ones that will pop your eyes out are the 395 corridor on the Eastern side of the Sierra Nevadas. Lee Vining, $7.19 for regular and $8.89 for diesel is what the Google said right now.
    • newdude
      2020 Trailboss 6.2 replacement

      By newdude · Posted

      Correct.  2019-2021 model years are serviced by a different p/n.  19420611.  Recall 2021s use 19420611.   The recall engines 2022-2024 model years are serviced with 12740076.     The difference between 19420611 and 12740076 is GM changed injector size for 2022.  The injectors are smaller on 12740076 with smaller injector bores in the cylinder heads to match the smaller injectors.  So you can't install a 19420611 in a 2022-2024, and you can't install a 12740076 in a 2019-2021.     Both engines are the replacement engine p/ns that are in the L87 recall.  So both of these are the updated engines.     Here's a version of the L87 recall with the p/ns for all the parts needed.    RCRIT-25V274-7075.pdf   Note it shows 19420611 and 12740076 with an asterisk to a footnote "Use the VIN and the GM Electronic Parts Catalog (EPC) to determine which part to order if two or more part numbers are listed for the same part, as it may vary by vehicle options."    

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...