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84' 300TD Greasecar
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Discussion Starter · #1 ·
So the battery light came on in my wife's 300td a few days ago. Shortly thereafter, the battery was dead. I had it recharged, it's less than a year old and they said the battery was fine. There's a 3 ampere draw on the battery with the car off which seems very high to me. I took out each fuse one by one and checked the current but it never went down. Is there something i'm missing? Is there another fuse box besides the one on the firewall? Or should I start pulling relays/switches also? I just got the car out of the shop after having most of the a/c system replaced as well as new glow plugs installed. Could there be something related there? Anyways, any help would be greatly appreciated.
 

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3 amps is WAY too much draw. I think an acceptable level is something like 30 milliamps, and thats just to keep the radio memory alive. Try unplugging the alternator and the glow plug box and see if that kills the draw. If not, then you can start unplugging relays. I think all of them are on fused circuits, but it won't hurt anything.

Jamie
 

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Battery drain

I had the same problem with my Ford F-350. I had just put in new glow plugs and found out that one was faulty in turn draining my batt. Start from there and like JamieK stated try unplugging your alternator. Remember always try the easiest method first unless your luck is like mine. I always have to go the hardest method and the most expensive way to find problems.
Lets us know how you make out.....
 

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'82 300D
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Have the alternator checked as well.
 

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1984 300CD
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rrgrassi said:
Have the alternator checked as well.
FWIW I agree. Alternator or the regulator built into it.
 

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84' 300TD Greasecar
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41 Posts
Discussion Starter · #6 ·
Yup, turns out the wires going into the switch on the alternator had worn through the plastic and were touching eachother. After cleaning them off and re-wrapping them the draw went away, the battery light went off, and now everything's fine. Thanks for the help.
 
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