I have been having some fun tracking down a black hole of a current drain that has toasted a battery of mine.

Symptoms
With the ammeter in series between the + pole of the (charged) battery and the distribution bus, the current draw is 160mA (with the car not running). Removing the fuses one at a time will only drop the draw down to 140mA or so (can't remember which fuse - I don't think it really matters).

So, I checked which of the wires [IMG]coming off the power distribution bus have current flowing....and low and behold, it is the small red wire shown on the photo as disconnected with the cracked black loom. (If the photo doesnt' make it, it is the top wire on the middle of the three terminals of the power distribution buss. The wire then heads down towards the firewall under the battery.) The resistance of this connection to ground is 2kOhms for what it is worth.

My wire diagrams don't indicate what this wire leads to - or I can't read the diagrams - which is a possibility.

ANYONE KNOW WHAT THIS WIRE DOES? EGR? Something unneeded?

The car seems to start and run normally with it disconnected. And no more 160mA drain.

All this is from an 84 300TD, with 260kMiles and a new starter and battery.

[IMG]DVC00264.JPG[/IMG]

Attached Thumbnails

 

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84 300TD - 235k - Farbe "Surfblau" bought at 213k
87 300SDL - 131k - Farbe "PimpGold" bought at 115k
00 Klepper Faltboot Expedition Double

Be sure to have a thorough look at all of the facilities, including trunk and glove box lights. One of the switches could be faulty, allowing the lamp to remain on even with the trunk or glove box closed.

With the wire removed, what no-longer works?
If you don't notice anything which has stopped wprking, just tape the wire up and forget it.

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Tony from West Oz.
Fatmobile 3 84 300D 295kkm Silver grey/Blue int. 2 tank WVO - Recipient of TurboDesel engine.
Josephine '82 300D 390kkm White/Palamino int.
Elizabeth '81 280E, sporting a '79 300D engine.
Lucille '87 W124 300D non-turbo 6 cylinder OM603, Pearl Grey with light grey interior


Various parts cars including 280E, 230C & 300D in various states of disassembly.

Thanks for the quick response. All the glove box lights etc are fused (I think). I removed all fuses one by one and they didn't seem to decrease the draw.

I didn't notice anything that didn't work- that is what puzzles me.

thanks

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84 300TD - 235k - Farbe "Surfblau" bought at 213k
87 300SDL - 131k - Farbe "PimpGold" bought at 115k
00 Klepper Faltboot Expedition Double

Just insulate the wire and don't worry about it. It will be there if you do find what it feeds, and you need to reconnect it after fixing the problem.
Tony

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Tony from West Oz.
Fatmobile 3 84 300D 295kkm Silver grey/Blue int. 2 tank WVO - Recipient of TurboDesel engine.
Josephine '82 300D 390kkm White/Palamino int.
Elizabeth '81 280E, sporting a '79 300D engine.
Lucille '87 W124 300D non-turbo 6 cylinder OM603, Pearl Grey with light grey interior


Various parts cars including 280E, 230C & 300D in various states of disassembly.

That doesnt look like an original wiring. All original wires to and from that conduit are wrapped with black plastic tubing. Could be an after market accessory, a mobile phone, stereo..?

I am going to have to agree with this. Does it sneak into the back of your stereo or something of the sort?

Wow, is that a regulation Mercedes battery? Nice....

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

I will check out if the old carphone was maybe connected up to this line. That would explain.

I noticed the tach stopped working after I disconnected the mystery wire. I was also testing wires in the neighborhood of the AC compressor, so maybe I accidently did something to the tach pick up.

So, I still have a little more investigation to do, but the outcome looks better since I drove about 650 miles this weekend with no problems.

thanks

alec

__________________
84 300TD - 235k - Farbe "Surfblau" bought at 213k
87 300SDL - 131k - Farbe "PimpGold" bought at 115k
00 Klepper Faltboot Expedition Double

It looks like the wire goes to the tach. It seems weird to me that one side of the tach is connected to a "hot all the time" terminal, but that is what is going on.

__________________
84 300TD - 235k - Farbe "Surfblau" bought at 213k
87 300SDL - 131k - Farbe "PimpGold" bought at 115k
00 Klepper Faltboot Expedition Double