Chevrolet 2007 TrailBlazer Owner's Manua page 97

Battery Replacement
Under normal use, the battery in your RKE
transmitter should last about two years.
the battery is weak if the transmitter does not work
at the normal range in any location. If you have
to get close to your vehicle before the transmitter
works, it is probably time to change the battery.
The Driver Information Center (DIC) will display a
KEY FOB # BATTERY LOW message when
the transmitter battery is low.
Notice: When replacing the battery, use care
not to touch any of the circuitry. Static
from your body transferred to these surfaces
may damage the transmitter.
To replace the battery in the RKE transmitter do
the following:
1. Insert a thin coin in the slot between the
covers of the transmitter housing. Gently
pry the transmitter apart.
2. Remove and replace the battery with a
three-volt CR2032 or equivalent battery.
3. Align the covers and snap them together.
4. Check the operation of the transmitter.
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