Review on Genuine GM Parts 15-81773 HVAC Blower Control Module by Christopher Pfaffe

I bought this item for my 2003 GMC Envoy XL. This car is equipped with GM's automatic temperature control. My problem was that the fan ran at a very low speed and sometimes STILL WORKED WITH THE IGNITION OFF, EVEN IF THE KEY WAS REMOVED. After several searches on the internet, the car's symptoms matched a faulty blower resistor package; However, since my car's climate control was "automatic", I needed a [more sophisticated] fan control module. The first is used when the fan speeds are manually adjusted and vary (e.g. 1-2-3-4) and the second is used when the fan speed is steplessly adjustable. In any case, their function is to reduce the 12 VDC supplied to the fan motor to the voltage required for the desired fan speed. Both types look very similar and reduce fan voltage by shunting some of it to ground via resistors. This shunt to ground generates a lot of heat. As such, these units are typically mounted on the fan exhaust duct and have heatsinks/fins that protrude into the duct for cooling. I searched YouTube for "GM Fan Control Module Replacement" and found a VERY USEFUL video showing a full replacement. Process using this specific Delco AC part. Note. This part uses an updated design (with more heatsink material) and the dash fan control connector does not fit; HOWEVER, an upgraded splice connector is included in the package. The instructions are simple, clear, and concise (and the font is larger than average). EVERYTHING YOU NEED was in the box. I chose to make my connections with wire nuts so I had to put those in ;-) All in all I can't imagine AC Delco could have done anything else to make this replacement part easier to use.