1992 400e Battery Drain

[ohiomike]

I have new battery and charging system pumps out about 14 volts so that is good. Problem is when car sits overnight (8hrs) the battery gets drained of voltage and won't turn starter.

Using digital voltameter I have isolated circuit controlled by fuse "C" (rear roof lights. trunk light, central locking, door lights, reading lights & Antenna). When I remove fuse no discharge occurs.

As a test I removed all light bulbs, door & trunk & hood switches, then inserted fuse back in. Result is I still have a drain on the battery (about .25 volts per hr). I sure hate to take car to stealership. Any ideas?

[Rick Miley]

Vacuum leak causing the central locking pump to keep running.

[ohiomike]

Since last post I have additionally disconnected the antenna motor, the vacuum air Pump for door locks connection, the relay there, the overhead reading light assy. (Left the other items mentioned before disconnected, too) I still have battery drain somewhere. A real puzzler. Any other ideas appreciated.