Scan Tool Diagnostics
WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 1999 GMC Yukon, 1999 GMC Suburban, 1999 GMC Sierra, 1999 GMC Pickup, and 1999 GMC Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
Scan Tool (Tech 2) reads and clears current and history codes. Ensure scan tool contains correct software cartridge for SIR diagnostics. To use scan tool, connect it to DLC connector, plug in power source and turn ignition switch to RUN position. Follow scan tool manufacturer instructions for communication with SIR system. Scan tool reads serial data from SDM data link output terminal No. 5 to DLC connector terminal No. 9.