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Major Electric Issues (2005 Suburban)

Discussion in 'Audio, Video & Gadget Tech' started by vinnysorrentino, Aug 5, 2012.

  1. vinnysorrentino

    vinnysorrentino New Member

    So I'm looking for some help with someone who understands the chevy electric system. About 2 years ago my Suburban started blowing hot air out of the ac. It was very spastic and not consistent so I didn't think much about it. Then about 6 months ago my driver side controls started only blowing max heat and passenger max cold. There was no way to change this as the controls don't work anymore. Now to make matters worse, when I turn off the vehicle the system continues to blow at full strength. The only way to turn the system off is to manually disconnect the battery every time. I've given up and am driving my other car for the time being because this is far too frustrating.

    Does anyone have any idea as to what could be causing this? Also, is there any way that I would be able to fix it without taking it to a shop?

    On a side note, around the same time my ac started acting up, my driver gauges (speedo and oil pressure) started spazzing out. Speedo thinks that 0mph is 100mph and takes it from there, oil gauge is pointing straight down. Don't think they are related problems, but wanted to include that just incase it is.

    Other than that, the car runs perfectly

    Thank you!
  2. zigger215

    zigger215 New Member

    Hello. I'll address both of your issues.

    First things first. Your AC situation. You're having two problems. The first one is your control switch has gone out, it's also called hvac control. Basically it's your control assembly switch in the dash. Replace that

    Second, your blower motor resistor has failed, it's very common in our GM vehicles for this to happen. I just had it happen in my silverado. This resistor is located in your blower motor housing, it's a little module screwed into the house with 9/32 bolts, your harness plugs into this. Remove it replace it and your hvac worries will be no more!!

    Your gauges. Our trucks have a common problem with stepper motors, this are the little motors that control our dials, they fail often. Look into getting your gauges rebuilt, that's the best solution.

    Any questions or clarifications feel free to reply, it's late and I'm tired so who knows, I probably confused you.
  3. Pikey

    Pikey Moderator Staff Member ROTM Winner 1000 Posts

  4. PantheraUncia

    PantheraUncia Active Member 1000 Posts

    I saw their site before,are they legit? :) website is a little less than average.
  5. Pikey

    Pikey Moderator Staff Member ROTM Winner 1000 Posts

    I just ordered a stepper motor from them. It arrived to my house in 3 days.(Form Texas to Michigan) It was packaged well and had a business card in the box for the company. They seem pretty legit. They are running a special for $100 for a complete rebuild if you pay with postal money order. That makes me nervous. I would pay the $125 with paypal, that way you are kind of covered
  6. RayVoy

    RayVoy Active Member 1000 Posts

    Vinny, we have 2 models of HVAC assemblies, manual (sliders, or knobs are moved from red to blue), or automatic (the temp is set to a degree and the HVAC attempts to keep it there). From your description, you have the automatic HVAC.

    The automatic HVAC uses a transistor (FET) assembly to control the blower fan. If you replace the Blower Motor Control Module, it will solve your blower problem. BTW, it is mounted very close to the blower motor, under the dash on some trucks, under the hood on others, usually on the passenger side of the truck.


    The hot and cold air adjustment control is accomplished with small motors that move doors (the motors are called actuators). There are a number of actuators, the ones you are having problems with are called temperature actuators and there is one for the passenger temp and one for the driver temp.

    Sometimes they can be reset by disconnection the battery (or pulling the HVAC fuses); but, it sounds like you have had the battery disconnected a number of times and they are still stuck. Try turning both dash controls to full cold and pull the fuses (or disconnect the battery), if that fails, try full hot and disconnect.

    Chances are, that the reset will not work; in which case, the actuators need to be changed.


    The others are right on with the stepper motors in the dash cluster. GM has been know to replace them for some year trucks.
    Last edited: Aug 15, 2012

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