jhartmac

Thank you for the information, however I have not installed the new seat modules basically have left them disconnected does that still apply? or were you referring to when you had them replaced it needed 24hrs..........

mleskovar

Then it's not the seat modules. Another source could be the overhead console. BKLYN_C's advice was right on..."Get an AMP meter and one by one disconnect all the systems (unplug fuses). In the matter of 5-10 mins you will know the place of drain." Put the amp meter in series between one of the battery cables and a battery post. With a drain you should read xamps/milliamps....you should notice a drop close to 0 when you open the offending circuit by pulling the fuse (I believe a slight draw is normal). 6 hours to a dead battery is a big drain.

coin

I was referring to -- after I had them replaced the module.

TruTaing

So your battery is STILL draining even after you replaced the seat modules? If so, this would imply that its not your seat module eating up your battery. Im just a little unclear as to what you are trying to say.

s1mple

jhartmac, when you installed your seat modules did you have to remove your seats, because you said you would try it w/o removing the seats first. and was it an easy install? i'm having seat modules problems on my 01 C320 also. i have taken out all seat fuses, left the car for 2 days and still no drain. this stupid car is getting me sick one problem after another seems like it. ac screws up, seat modules, now crank sensor has to be replaced.GG <3 benz.

oh and did you replace both your seat modules?

jhartmac

Actually I have not yet replaced them, havent even purchased them yet...............and I believe you are correct about disconnecting each fuse, I hope the one that is bad it not running more then one thing in the car, secondly, does anyone have or know the schematics of the fuses? the cover -which normally shows what each fuse controls is NOT on the inside...............crazy right? most cars have this information on a lable on the inside of the fuse cover.

s1mple

there should be a picture of the fuse diagram in the fusebox inside the car next to the steering wheel.

jhartmac

How about the fuse box under the hood?

TruTaing

The printout of the fuses near the steering wheel should have diagrams for all the fuse boxes and what features require what fuses.

Search and you can find a scan of the printout on these forums or the "other" forums.

QK37

My battery is still draining after I changed both seat modules. Does anyone have an idea what's going on? I went to Motorwerks and they said they couldn't find anything, they advised me to go back MB dealer and have time to run full check. Please give me some advice!!!

jhartmac

QK37- your getting the proverbial D broken off in your A.......... welcome to the new Mercedes Benz, its seriously a joke to have a 50k car and have issues like this..................CAR AND DRIVER just BUSTED MERCEDES, one of the worst vehicles to own as far as issues are concerned, so buddy, it looks like you and I are F(*& honestly I wish I would have bought a BMW or Lexus, what a joke............and theres folks on here NOT EVERYONE that stand by MB like its GOLD well I guess they havent had problems like this or maybe they just too stupid to keep paying for issues that they shouldnt have to.

Ok now help with your issue, try using a multimeter hooked up to your battery, 12 volt DC, you will probably notice it loosing voltage slowly, now find your fuse box, start with the one inside the cabin, near the steering wheel, disconnect one at a time and see if your multimeter stabilizes the voltage, it should maintain 12 volts period, after you find the problem, or I should say hopefull you will, start the car and you should see 14.4volts now............that means your altenator is functioning properly. I am about to start this process today..........see what I can find out, I dont have deep pockets like alot of these guys on here............they like going to the dealer and getting F(*&^ and liking it.........not me.

mleskovar

[QUOTE=jhartmac;2053074] try using a multimeter hooked up to your battery, 12 volt DC, you will probably notice it loosing voltage slowly, now find your fuse box, start with the one inside the cabin, near the steering wheel, disconnect one at a time and see if your multimeter stabilizes the voltage, it should maintain 12 volts period,QUOTE]

You'll never find it that way,....hook up the multimeter in the amp mode, take the negative terminal off the battery, then put the meter leads between the negative post and the cable (in series). You should see a steady current draw...I don't know how much but you can do the math. When you pull the fuse from the offending circuit then you'll see the needle drop immediately. There's some current always being drawn I believe...very minimal.

C230 Sport Coup

[QUOTE=mleskovar;2053427]Correct or use a current "shunt", and accessorie for your multimeter that just goes over the battery wire.

jhartmac

I will be checking mine today- I have a digital FLUKE multimeter, not an analog-needle.........last time I hooked up the meter to the battery POS TO NEG I saw a steady decline of VOLTAGE-DC, however in AMPS as you suggest I will probably need a ANALOG meter to see the "spike" in AMPS.

mleskovar

Digital is OK. When you first hook it up just note the current draw. 230 Sport Coup is correct, a shunt/clamp would be easier

QK37

I have no problem since I disconnected both seat modules. So, I guess the drainage may come from the either seat or both. And I am going to try to connect them back in one by one this weekend and see which is the main cause of my drainage problem. By the way, thank you for all your comments...I will definately try sometime!
And I really love my car except these stupid problem.

jhartmac

Ok follow up, and found the culprit, 1st of all let me state, if you remove the negative battery terminal you will ONLY find a ground short!!!!!!!!!!! you will NOT find a short with a particular electrical item- seats, lights whatever, that is because those items most have a + and - to actually be working or in this case DRAINING YOUR BATTERY. Now for the update, after using my mulitmeter with the NEG battery terminal or wire off I found NOTHING the amps stayed continuous, however when I reattached the NEG battery wire, I noticed a -1 amp loss every 3-4mins, with my seats unplugged no less the whole time, so I went to the fuse schematic and looked for the Command SE unit, that would be fuse #64 found on the drivers side fuse box under the hood, pulled that fuse............the meter stayed at 5.5amps no more problems, plugged the seats back in one at a time and kept an eye on the meter at 5 min intervals..........NO PROBLEM, so with all that said I was back to the original FREAKIN problem I thought it was from the very begining, the cooling fan is continually running, not going on shut down or automatic shutdown, unfortunately that cooling fan in the unit is not on its on circut so right now I have NAV, No Radio, which really sucks, does anyone have a fix to this problem??

mleskovar

I'm sorry, I can't figure out what you're talking about for the life of me. It sounds like you disconnected the battery ground strap and tried to find a short by pulling fuses? That won't work, evidently you found that out. How did you measure a 1 amp loss (how did you have the meter hooked up)??? What cooling fan are you referring to?

jhartmac

Per your quote:

You'll never find it that way,....hook up the multimeter in the amp mode, take the negative terminal off the battery, then put the meter leads between the negative post and the cable (in series). You should see a steady current draw...I don't know how much but you can do the math. When you pull the fuse from the offending circuit then you'll see the needle drop immediately. There's some current always being drawn I believe...very minimal.

Simply broken down, a FLUKE 73 multimeter set on AMPS-DC positive hooked to the positive battery terminal, negative hooked to the negative battery terminal, the reading started at 5.5amps DC slowly as stated before it displayed a -1amp loss per 3-4 minutes as in start at 5.5, to 5.4 to 5.3 etc............so on and so on, once I removed the 10amp fuse for the Command Unit, the meter no longer showed a loss but stayed at 5.5amps DC.

mleskovar

What you were reading was the current draw of the meter! Remove negative terminal...put the meter in series between the negative terminal on the battery and the negative clamp you just removed. That would be your current drain...it should be zero or close to zero (very small, I'm not sure). If it's not zero (and something is drawing current) you pull fuses until it goes to zero. That would be the fuse of the offending circuit.

nilknarf

I'm having the same problem with my '02 C230. I removed the negative terminal and put an ammeter in series between the negative terminal on the battery and the negative clamp I removed. My reading was 0.0. However, after hooking the battery back up, and driving the car, I'm now getting a steady voltage drop over the course of several hours...about 1/2 Volt per 12 hours.

Now I did read somewhere that with modern circuitry, that components can shut down when the battery cable is disconnected and won't necessarly come back to life when you hook your ammeter up. For that reason, a shunt is recommended (also to protect your ammeter). I saw that a couple of you guys also recommended using a shunt.

I went to a couple of auto parts stores today looking for a shunt and nobody knew what I was talking about. I did find a lot of shunts on ebay, but have to idea what specs I need. Can anybody recommend one, or post a link? Thanks!

silver_benz

If you measure Volts by hooking your meter to the positive and the negative posts of the battery, you will recieve very little information about the draw on the battery. If you measure Amps by hooking your meter in-line with your battery (disconnect one battery cable and hook one end of your meter to the battery cable and the other end of your meter to the battery) and using the meter to complete the circuit, you will measure the amount of draw (measured in amps) on your battery. If you have an analog meter, be sure to connect it correctly and initially set the amperage at the highest rating. If you connect it backwards, your needle will peg backwards and could damage the meter. If you connect it with the amps set to the lowest setting, you could peg the meter on the high side and possibly cause damage. My question is this: What is the normal draw on a battery with the key removed and all systems off? I have a 2001 c320 that recently started with the battery problems.

nilknarf

I could never get a amperage reading..always 0.0, so I just unplugged my RF seat control module and voila, no more dead batteries. In fact I left it unplugged for two months with no battery drain and then bought a new RF seat control module...plugged it in and no problems since.

ML55CLA45

if any of you guys need a new control module... let me know.

i have a front drivers side for sale. purcahsed from the dealer. thought it was the solution to my seat not moving completely forward/reverse. ended up being a seat motor problem.

dont know the truth behind this... but when i purchased the drivers side the dealer tried to sell me the front passenger side as well. was told that if you upgrade one control module you need to update the other.

i did not purchase the other side because i was not having battery draining problems.

its brand new in the box. i have the reciept and i purchased it for over 300 bucks.

if interested ill make you a heck of a deal.

-charles carino

charles@carino.com

deloreandriven

+1