The transfer case control module (also sometimes called the transfer case actuator or shift motor) in a 1998 Chevy Blazer is typically located
on the passenger side of the transfer case itself. It's a relatively small, electronic module often attached directly to the transfer case with bolts. You'll likely need to get under the vehicle to see it clearly. It's usually near the rear driveshaft connection to the transfer case.
However, the exact location can vary slightly depending on the specific transfer case and options installed on your Blazer. A repair manual specific to your vehicle's year, make, and model will give you the most accurate location. A diagram in the manual will also be very helpful.
