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Discussion Starter #1
Something is draining the (new) battery - if i don't drive for a day it's dead.
Two of the relays (E & F) are hot after a ride. Anyone knows what these relays are for and is this a good indicator of the problem?

Since my wife is taking kids to school, she is more than frustrated when she can't start the engine in the morning.

please help!!!
thanks :bowdown:
 

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Something is draining the (new) battery - if i don't drive for a day it's dead.
Two of the relays (E & F) are hot after a ride. Anyone knows what these relays are for and is this a good indicator of the problem?

Since my wife is taking kids to school, she is more than frustrated when she can't start the engine in the morning.

please help!!!
thanks :bowdown:
Not an answer, but I bought a trickle charger for around $30 (water-resistant is around $40). Mine dies after four or five days if I don't drive it. I havent' tracked down the drain yet, so this is a temporary fix. You can attach it permanently to your battery, and just plug it into the socket without having to pop your hood.

eBay Motors: Battery Tender, Water proof, 12V .750 amp Outdoor use! (item 350025522016 end time Feb-20-08 09:23:47 PST)
 

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Something is draining the (new) battery - if i don't drive for a day it's dead.
Two of the relays (E & F) are hot after a ride. Anyone knows what these relays are for and is this a good indicator of the problem?

Since my wife is taking kids to school, she is more than frustrated when she can't start the engine in the morning.

please help!!!
thanks :bowdown:

Welcome, to take advantage of all the forum features, please re visit the 'Welcome to the Forum' tutorial sticky on top of the W126 page, as well as the two DIY stickies.
It will show how to search the forum, and even has a link to the Russian MB site where you can run a VIN#. The forum archive has a wealth of information re your topic.
Good luck

Please complete your profile with a location and car mod (see sticky for how to). It makes it easier for member to offer advice.
For example, the vacuum diagram for a Euro will differ from the US version.
Cheers
 

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Could be the battery itself, Or the alternator going bad.

I haven't tried this myself (haven't needed to) Start the car and then remove the negative battery connection, If the car shuts off, I think that means it needs to be replaced (hopefully someone's able to confirm this method).
 

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Discussion Starter #5
Not an answer, but I bought a trickle charger for around $30 (water-resistant is around $40). Mine dies after four or five days if I don't drive it. I havent' tracked down the drain yet, so this is a temporary fix. You can attach it permanently to your battery, and just plug it into the socket without having to pop your hood.

eBay Motors: Battery Tender, Water proof, 12V .750 amp Outdoor use! (item 350025522016 end time Feb-20-08 09:23:47 PST)
thanks, but i don't quite get it how this thing work? :confused:

btw, battery is brand new and alternator was checked and it's ok
 

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thanks, but i don't quite get it how this thing work? :confused:

btw, battery is brand new and alternator was checked and it's ok
If your alternator is good and your battery is new, then it's confirmed you have a drain somewhere.

It's got to be a major one if it completely drains the battery overnight. An interior light left on would not be able to drain a fully charged battery in 24 hours.

I'm not sure the warm relays is an indication of anything. If they were hot, I'd worry, but merely warm isn't really an indication of anything wrong.

Any recent work or the car? Such as a new stereo unit put in by a "professional" at Circuit City, Best Buy, or some such?

If not, try to remove the fuse from suspect circuits overnight to track down the culprit by process of elimination.
 

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I use battery tenders when I don't drive things for a while. Instead of using the alligator clips, there is an alternate wire that comes with the kit where you hard-wire to the positive and negative battery terminals. At the other end of the wire is a connector which plugs into the charger itself (or alternately you'd plug the alligator clip wire in here). So the nice thing is you can simply plug/unplug that connection when you go to drive the car without having to pop the hood each time assuming you run that wire from the battery up near the wipers where its easily accessible (or another accessible spot). Just remember to also unplug the charger itself from power unless there's an on/off switch.

Axel's suggestion on removing fuses one by one each night is probably best at this point. If you want to "speed it up" remove 3 or so at a time and at least then you have it narrowed down to one of those 3 if the problem ceases when they are removed overnight.

Good luck!
 

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Discussion Starter #8
...the only "work" i've done recently is my two little boys jumping, kicking, pulling, ripping and braking everything possible in the car....stereo dosn't work, seat heaters don't work, interior lights as well, and so on....
...but that's why i bought this car - it is the only one that can sustain my boys and still run!
as to worm relay, someone told me that is an indication what is draining the battery; there are 5 relays - a,b,c,e,f; only e and f are worm after driving, others are chili cold.
 

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If the relays were warm after sitting overnight, you've got something.

That the relays are warm after driving (just warm, not HOT), doesn't mean anything.
 

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Pull the relays and see what doesn't work..I've seen seat switches/master relays go bad and cause this sort of thing to happen.


Jonathan
 

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I have something similar going on, i think...
Just the other day while driving the radio went out and i couldn't turn it back on. I then noticed a bunch of the "idiot lights" were on (abs, srs, etc.) and the needles in the gauges were dancing and jumping all over the place. I pulled over and noticed the engine was actually revving with needles and I really had to step on the brakes to keep stopped. I put it into neutral and the throttle went wide open. I put into to park and engine cut out and wouldn't start again. Got a jump and ran the engine for a while, then I drove about a mile before the whole thing happened again.
Recharged the battery and drove to work just fine the next day. On the way home she died almost immediately.

Any thoughts?
 

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Oh, the trials and tribulations of married life!! But when you told me how your wife is frustrated and your kids wreck your car, you gave me more information than I wanted to hear. The same thing happened to me when I was married, and it was a sign of bad things to come. I am willing to give you some advice on this, if you don't think I am sticking my nose into your business. If you'd like to hear my experiences in this regard, please PM me. I think you could benefit from my very similar experience. But all you really need to post is what's wrong with your car, OK?

With the engine off, disconnect the negative battery lead and connect, preferably, an ammeter between the negative battery terminal and the battery lead. If you don't have an ammeter, you can use a test light. If current is flowing, remove the top from the fuse box and remove each fuse, one at a time, until the current draw goes away. Now you know which circuit it is in.
 
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