Chevrolet has three independent sunroof drains on vehicles, such as the Chevy Equinox. The first drain is behind the plastic molding located beside the rear passenger side seat. The other two are located on the top front side of the sunroof. All of the vents drain into the wheel wells of the car. These vents clog up when debris on the sunroof glass gets pushed onto the sunroof seal when you open and close the sunroof.
Open the sunroof and the rear passenger side door. This gives you access to all of the drains on the Chevrolet.
Remove the plastic molding starting at the floor on the rear passenger side and working your way up until you can reach the rubber tube that goes into the fender well. The molding does not bolt into place; rather it is held in place with plastic clips.
Pull the rubber tube out of the fender well and place the nozzle of an air compressor hose into the tube. Spray air into the hose until you can hear air exiting from the sunroof. This indicates a clear passageway.
Press the hose back into the hole in the fender well then snap the plastic molding back into place.
Locate the two air holes in the front of the sunroof. Each air hole is located just above the rubber seal in the front corner of the sunroof track. It is roughly the size of a paper hole punch. There is one hole at each of the front corners.
Place the air hose nozzle against the hole and blow compressed air into the hole until you hear air expel from the front fender well. Do the same for the second hole.
Remove all of the debris from the rubber seals and track to prevent clogging the water drains again. You can use the compressed air to clean the rubber seals and track as well.