Battery Advice Needed

[BillyBoy]

Hi,
I got back to the train station last night to find my battery was flat and wouldn't start the car. It's been a bit sluggish for a couple of days, and I suspect the battery may be shot.

I'm going to get a new one and fit it, but have seen a few horror stories about changing batteries on cars, and wonder if there are any precautions I need to take other than disconnecting the old one and fitting the new one?

The car is an S320 CDi (W220) 2004 face lift model.

Cheers,
Bill

 

[television]

Hello Bill, no problems on your car on changing the battery.
Do buy a good make like Bosch, Banner,Exide, Lucas Varta.

Do not get a Halfords or other in house name for peace of mind

 

[BillyBoy]

Thanks Malcolm

KMS have genuine Mercedes ones (made by Bosch I believe) for £89 +VAT which seems pretty reasonable to me (£60 less than the local Merc dealer), so I'll pick on up tomorrow and fit it.

Cheers,
Bill

 

[tromppost]

You may have to reset the one touch windows and sun roof after the battery has been changed. Your right about getting a good qualty battery it always pays in the long run.

 

[television]

You may have to reset the one touch windows and sun roof after the battery has been changed. Your right about getting a good qualty battery it always pays in the long run.

Yes age is getting the better of my memory, the ESP lamp will be on, just turn the steering from lock to lock 3 times and re set the windows and roof by holding the button said button closed for 10 sec in key2


Thanks tromppost

 

[Cole@MBS]

It will also say "pre-safe in-active" Your have to drive it 100 yards up the road, re-cycle the ign to clear it

 

[BillyBoy]

Thanks guys - I remember the ESP and windows etc. from when I replaced the battery on my E-Class - that didn't have pre-safe though, so useful tip on that too.

When I jump started it last night, I found the steering wheel wouldn't go all the way up. Is this linked to the Pre-Safe too?

I also found it's worth shopping round. My local MB dealer wanted £163 for a new battery - the one by work only wants £111, so I'll get one from there tomorrow as it's only a few quid more than KMS, and saves a trip into B'ham.

I remember a similar experience with Ford many years ago where I saved over 40% on a headlamp washer pump just by going to a different dealer! I guess it's worth remembering these are franchises, so can charge what they want (though presumably MB give some guidelines)

Cheers,
Bill

 

[BillyBoy]

Looks like it isn't the battery:-(. I fitted a brand new MB one on Wednesday, and took the car for a drive round for half an hour. Left it until this morning (Saturday) and although it started, it was very sluggish to turn over, so looks like I have a battery drain.

I do have a car phone kit (OEM with Nokia 6310), but the phone does turn off after about 10 minutes when you stop. I have constructed a plug in current tester that plugs in to the fuse slot to check the current through it (Made from an old fuse and a couple of banana leads to plug into my multimeter). Are there any common problem areas to check first before I just start pulling fuses at random?

Cheers,
Bill

 

[mike4444244]

Costco are ectremely cheap for bosch batts and they have a no quibble 5 year warranty, I'm on my 9th and 10th from them in 4 years (killed them winching the defender )

 

[television]

The seat controllers are one known sorce of battery drain

 

[HERBIEMERCMAN]

hi billyboy, nearly 30% of batteries are changed in winter months and there is nothing wrong with them, because 70% change their battery and all is well then folklaw says that's what you should do. first thing to do is put the battery on charge overnight, 3 to 4 amps, it then takes ten minutes to check your battery condition, you can visit a friend who has a multimeter for measuring amps / volts or your local garage, it doesent need to be an auto electrician. at a certain load the voltage decays and on a duff battery with a cell down the readings are obvious. if the battery passes the test you then put the meter on and see what current is being drawn with everything switched off, this will establish if there is a leakage current, if there is then the hard part is locating it, but at least you have not wasted your money on a battery you did not need.finally you measure the output from your alternator circa 16 amps at 1000 rpm. many people who have a 5 yr old battery are running on only 25% of their batteries capacity as all batteries sulphate on the plates from the bottom and only the top 25% of the plates are still active, voltage is ok, current, starting, but short runs, or leaving a light on etc. soon exhausts the reduced capacity. in winter all batteries loose up to 20% of their potential when tempperatures drop. hope you find this info. usefull. herbiemercman.

 

[BillyBoy]

Annoyingly, the car seems to have righted itself at the moment. I've been away a few days with the hope of sorting it out when I got back, but it now appears to not be draining. Here's possibly a clue that someone may recognise as the cause of the fault though.

The fault appeared when we had the really cold weather a couple of weeks ago. When I downloaded my snow pics today, I found the attached. This was taken in the morning after the car had been standing all night (from about 6 o'clock the previous evening) Note that the snow has melted over the sensor cluster from in the rear view mirror housing. This would indicate a heat source here - is this normal, or could it be a fault somewhere here?

Also, does anyone know where I can find the fuse allocation for my car (W220) The hand book says it's in the boot with the spare fuses and toolkit, but I have nothing there that I can see.

Cheers,
Bill

 

[Cole@MBS]

Its should be in the boot,

Going back to your draining fault, i have in the last month seen 4 differnt mb,s all going flat overnight, cause, nokia 6310! turns off and wakes up 10 mins later!

 

[popuptoaster]

When you changing the battery can you not put a battery charger onto the leads as you swop batteries to save all the resetting of stuff? or is that a daft idea?

 

[Cole@MBS]

Good idea Popuptoaster! trouble with that is the positive termainal is right next to the rear wheel arch, and the battery is in there so tight, you would probley knock it of everytime!

 

[television]

With a regulated 12 volt source and a cigar lighter lead plugged in, the key could be left turned to 1,, but a battery charger as we know it would blow many components with no car battery fitted