1996 Lexus GS 300 window switches / battery

You want to look for all possible drains on the battery. Check glove box light. Dome, under hood light if equiped, trunk light radio, fan or blower motors not shutting off. If you can find no items running then we need to put a meter on the battery with the engine off. Note the voltage then one by one pull the fuses in the cabin area. Watch for a noticible change in the reading on the meter. Remember to close the door before recording the reading as your dome light will mess it up. After you finish the inside fuse box and you dont see a change in the reading do the fuses and relays in the engine area. When you find the item that is draining your battery we can focus on that item.

Your battery should start out at about 12.5 volts fully charged. As for your window motors you can replace yourself just takes some time and patience. You should be able to find out if your window motors are draining your batt by the the method I explained above.

Let me know how this goes for you and dont hesitate to shoot any questions my way.