Buick 2004 Regal Owner's Manual page 173

The TCS operates in all transaxle shift lever positions.
But the system can upshift the transaxle only as high as
the shift lever position that was chosen, so use the
lower gears only when necessary. See Automatic
Transaxle Operation on page 2-21.
See Traction Control System (TCS) Warning Light on
page 3-33. Adjust your driving accordingly.
To limit wheel spin, especially in slippery road
conditions, you should always leave the TCS on. But
you can turn the system off if you ever need to. The TCS
should be turned off if the vehicle ever gets stuck in
sand, mud or snow and rocking the vehicle is required.
See Rocking Your Vehicle in If You Are Stuck: In
Sand, Mud, Ice or Snow on page 4-30.
While the TCS is on, the
TRAC OFF light could
come on the instrument
panel cluster to show that
the TCS is not limiting
wheel spin.
When the TCS is turned off, the TRAC OFF warning
light will come on. It will disappear when the TCS
is turned back on. If the TCS is limiting wheel spin when
the TRACTION button is pressed, the TRAC OFF
light will come on and the TCS will turn off right away.
To turn the TCS on or off,
press the TRACTION
button located directly
behind the automatic
transaxle shift lever on the
instrument panel.
4-11