Cadillac 2008 XLR Owner's Manual page 147

Adaptive Cruise Control might detect a vehicle that is
not in your lane and apply the brakes.
Adaptive Cruise Control might occasionally provide a
driver alert and/or braking that you consider unnecessary.
It could respond to signs, guardrails, and other stationary
objects when entering or exiting a curve. This is normal
operation. Your vehicle does not need service.
Highway Exit Ramps
CAUTION:
{
Adaptive Cruise Control may lose track of the
vehicle ahead and accelerate up to your set
speed while entering or on highway exit ramps.
You could be startled by this acceleration and
even lose control of the vehicle. Disengage
Adaptive Cruise Control before entering a
highway exit ramp. Do not use Adaptive Cruise
Control while entering or on exit ramps.
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