Chevrolet Repair: Battery draining in a few days, light timer, rearview mirror

Question
I have a 97 Blazer 4x4, V6. We have replaced the battery twice in 6 months. Now the new battery drains down in 2-3 days. When it is recharging (engine off) you can hear a chirping sound in the dash. If you press on the brake pedal everything goes dead (interior lights, etc.)Any suggestions?

Thanks

Answer
Hi Dan,
Charge the battery with the cable disconnected. Then rather than connecting the cable directly to the battery, connect a test light between the battery and the cable.
If it lights brightly, something is drawing power.
Leave it connected for about a minute, to allow any timer to time out, such as a dome light timer. Have the windows down, and the doors closed.
Unhook any under hood light, and then start removing fuses till the light goes off.
There is something that is drawing power all the time.
A light in the glove compartment, or the trunk, or the lights under the rearview mirror are all hard to see.

Here is a link that might help.

electric.articles.mbz.org/drain/

Van