Hummer 2009 H2 - Manual (Page 294)

Traction Control Operation
The traction control system is part of the
StabiliTrak system. Traction control limits wheel
spin by reducing engine power to the wheels (engine
speed management) and by applying brakes to
each individual wheel (brake-traction control) as
necessary.
The traction control system is enabled automatically
when the vehicle is started. It will activate and the
StabiliTrak light will flash if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If the traction control is turned off, only the
brake-traction control portion of traction control will work.
The engine speed management will be disabled. In this
mode, engine power is not reduced automatically and the
driven wheels can spin more freely. This can cause the
brake-traction control to activate constantly.
Notice: If the wheel(s) of one axle is allowed to
spin excessively while the StabiliTrak, ABS
and brake warning lights and any relevant DIC
messages are displayed, the transfer case could be
damaged. The repairs would not be covered by the
vehicle warranty. Reduce engine power and do
not spin the wheel(s) excessively while these lights
and messages are displayed.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens, a reduction
in acceleration may be noticed, or a noise or vibration
may be heard. This is normal.
If cruise control is being used when StabiliTrak activates,
the cruise control automatically disengages. The
cruise control can be re-engaged when road conditions
allow. See Cruise Control on page 3-12.
StabiliTrak may also turn off automatically if it determines
that a problem exists with the system. If the problem does
not clear itself after restarting the vehicle, see your
dealer/retailer for service.
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