Hi, My battery goes dead overnight. Tested the circuit and found a 0.15 m/a draw. Does not seem like enough to kill my battery. (Battery is new) tested all the bulbs by taking them out one by one and got no change. Pulled all the fuses out one by one still no change. Any ideas what could be doing this?

How old is the battery? It may be replacement time.

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Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

Maybe the voltage regulator has worn brushes or is plain tired. For the cost, just replace it.

Sixto
98 E320s sedan and wagon
02 C320 wagon

Check the battery by charging it and leaving one cable off. Put the cable back on the next day.. If still charged and will crank the car well. At least you then know if it is a car or battery issue. The sad part is that if it is the car you are also damaging the battery. Batteries no longer tolerate being well drained down anymore. Shortens their life I have found.

Could be the glow plug system is somehow intermittently triggering on. Certainly the current draw you quote will not matter with a good new battery overnight. You have a voltmeter. What voltage do you read with the engine running?

Similar to what Barry said. If it is an issue inside of the Alternator if you disconnect the Alternator Electrical Connector in the evening and the Battery is not dead the next morning it is something inside of the Alternator draining the Batter.

Note Harbor Freight Volt Meters are cheap and often free with some of the coupons.

Note I started and drove my Volvo diesel to a realities House and it was charging OK. Started and left that House and stopped to eat.
When I was ready to leave I turned the key and got nothing.

The short story is the Battery was finished. Walked across the street and bought another Battery and was off with no more issues since.

The Dead Battery showed 12.50 volts but had little amperage. Using a jumper wire between terminals I only got a faint spark.

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84 300D, 82 Volvo 244Gl Diesel

You could have a bad diode in the alternator that will kill a battery overnight. If you have a multi tester, its easy to check.

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96 E300d

Be careful when testing the charging system. I had the glow system show a non-charging situation when I had the car on a tester at the parts store.

You can approximate a load test by putting a volt meter on the battery and turning the key to start. A discharged battery will show a large voltage drop when under the load of the starter.

Search parasitic drain if you determine that the battery and charging system are good. There is much more available information than you'll get in a single post.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.