Circuit Description
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 1998 GMC Yukon, 1998 GMC Suburban, 1998 GMC Pickup, 1998 GMC Cab & Chassis, and 1998 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
Automatic Transfer Case (ATC) control module interfaces with 4 normally open push button switches. Switch assembly, located on instrument panel, uses a resistor network to provide analog voltage signal to ATC control module to determine 4H, AUTO (Adapt), 2H, N and 4L shift request. Control module supplies 8 volts to switch assembly through Light Green/Black wire circuit and reads voltage level back on Light Blue/Black wire circuit. When DTC B2725 is set, an open, short to ground or short to voltage condition exists, or switch assembly fault has occurred.