Cadillac 2011 DTS Owner's Manual page 121

To avoid arming the alarm by accident:
Lock the vehicle with the door key or the manual
door lock.
Always unlock a door with a key or use the RKE
transmitter system. Pressing the unlock button on
the RKE transmitter, or unlocking a door with the
key disarms the content theft-deterrent system.
Unlocking a door any other way will activate the
alarm when a door or the trunk is opened.
If you activate the alarm by accident, unlock the driver's
door with your key. You can also turn off the alarm by
using the unlock button on the RKE transmitter system,
or by starting the car with a valid key.
Changes or modifications made to this system by other
than an authorized service facility could void
authorization to use the theft system.
1. From inside the vehicle, roll down the window, then
get out of the vehicle, keeping the door open.
2. From outside of the vehicle, with the door open,
lock the vehicle using the power door lock or the
RKE system and close the door. Wait 30 seconds
until the security lamp goes off.
3. Reach in and unlock the door using the manual
lock and open the door. The horn will sound and
the hazard lights will flash.
You can turn off the alarm by unlocking the driver's door
with your key, using the unlock button on the RKE
transmitter or by starting the car with a valid key.
If the alarm does not sound when it should, check to
see if the horn works. The horn fuse may be blown. To
replace the fuse, see Fuses and Circuit Breakers on
page 6 103. If the fuse does not need to be replaced,
you may need to have your vehicle serviced.
To reduce the possibility of theft, always arm the
theft-deterrent system when leaving your vehicle.
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