2002 Chevrolet Blazer Owner's Manual - Page 79

To replace the battery in the keyless entry transmitter do the following: Rear Window CAUTION: It can be dangerous to drive with the rear window or endgate open because carbon monoxide (CO) gas can come into your vehicle. You can't see or smell CO. It can cause unconsciousness and even death. If you must drive with the rear window or endgate open or if electrical wiring or other cable connections must pass through the seal between the body and the rear window or endgate: D Make sure all other windows are shut. D Turn the fan on your heating or cooling system to its highest speed with the setting on VENT and OUTSIDE AIR. That will force outside air into your vehicle. See "Comfort Controls" in the Index. D If you have air outlets on or under the instrument panel, open them all the way. See "Engine Exhaust" in the Index. 1. Insert an object like a thin coin in the slot between the covers of the transmitter housing near the key ring hole. Remove the bottom by twisting the object. 2. Remove and replace the battery with a three-volt CR2032 or equivalent battery, positive (+) side up. 3. Align the covers and snap them together. 4. Check the operation of the transmitter. 2-13