Conditions For Setting DTC
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.
System will set DTC after system turns output on (grounds circuit) and detects a high voltage. System will not attempt this again during ignition cycle. ATC control module detects a high voltage when low voltage is expected on 4L discrete output (Gray/Black wire circuit). This condition may affect transmission shift points. SERVICE 4WD light will be on for remainder of current ignition cycle.