2003 Chevrolet Astro Owner's Manual - Page 93

To fully open the rear doors, push in on the clip and lift the check assembly up off the mounting bracket. Do this on each door. Replace the check assemblies on the mounting brackets before closing the doors. It can be dangerous to drive with the rear glass 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 glass open or if electrical wiring or other cable connections must pass through the seal between the body and the rear glass: Make sure all other windows are shut. Turn the fan on your heating or cooling system to its highest speed and select the control setting that will force outside air into your vehicle. See "Climate Controls" in the Index. If you have air outlets on or under the instrument panel, open them all the way. See "Engine Exhaust" in the Index. 2-14