gmtech2014

Each vented seat consists of 2 blower motors; one in the seat back and one in the seat cushion. During vented seat operation, the vented seat blower motors move cabin air through channels in the foam pad and small holes in the seat covers causing a cooling effect to the occupant. With the ignition ON, battery voltage from the ignition main relay is applied through a 15 A fuse located in the Instrument Panel Fuse Block to the seat cushion blower motors. Ground for each blower motor is provided through separate ground circuits and a common ground connection. When the seat heating control module receives a ventilation seat command, it sends a low side drive pulse width modulation (PWM) signal through the blower motor control circuit to the seat cushion blower motor indicating the seat ventilation command. The logic in the blower motors sets the blower speed to the switch set point. The blower motors run causing a cooling effect to the occupant. This is From GM service information and the description and operation

This is normal. GM calls it Afterblow. There are a few parameters that have to be met, but the jist of it is that the truck will keep the blower motor on for a set period of time after the truck as been shut off to dry off the evaporator core.

What accessory are you wanting to install?

If the fog lamp indicator did not light up previously and now does, they programed the BCM correctly.