Description & Operation: Notes
WARNING: This page is about a different car, the 1999 GMC Sierra and 1999 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
Vehicles are equipped with air bag supplemental restraint system. Before attempting any repairs involving steering column, instrument panel or related components, see SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG SYSTEM in AIR BAG RESTRAINT SYSTEMS
article.
CAUTION:
When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES
article in GENERAL INFORMATION before disconnecting battery.
The serial data line is the means by which the microprocessor controlled modules in the vehicle communicate with other control modules and the scan tool. There are 2 different types of communications used on this vehicle, Class 2 Serial Data and UART serial data.