battery fault

[shakeapaw]

got up this morning and when i started the car i was greeted with the message "consumer electronic's switched off ",it has also repeated itself this afternoon.
i obviously dont want to replace both batterys if only one is faulty,the car starts/runs ok so im thinking it must be the ickle battery in the engine bay.
so can i just change this battery myself,and at what cost,or do the local steelers have to do it if there is some sort of reset of equipment involved ?

 

[jtr]

I had this last winter on my E320CDi. A charge of the main battery sorted it out for a while but the problem came back. I had the same message a couple of weeks ago and it turned out that the main battery was finished and it has now been replaced.

 

[DITTRICH]

1 Did you leave any lights on?
2 Shutdowns occur when the car thinks it needs to save what stored power is left in the battery(ies).
3 Either a battery somewhere is not holding its charge (buggered) or something is draining the charge (consumers) or its not charging properly (a fault elsewhere - alternator?).
4 On the more modern complicated cars I'd be wary of changing something without first determining the cause. Sadly, I think you will have to visit a garage for a proper diagnosis.
5 Search the threads on the forum and you will get an idea of how long batteries tend to last.
My 2c
Les

 

[shakeapaw]

JTR,what was the cost of the replacement battery?

DITTRICH,i leave my autolights and wipers on all the time,ive just been out again and got the same message and then another one saying "turn lights off" and then the electric/heated seats seem to be locked out,though they could be used as normal about 10 mins later,if all of these electrical systems run through the main battery what does the little battery support ?

 

[television]

Your battery could be on the way out, or you could be doing some runs with everything turned on, like heated seat etc.

Always charge the battery before you test it or buy a new one, 4 years is not too bad these days for the life

Just buy a cheap voltmeter (under £10) and measure the voltage after it has been charged, it should be over 12volts the following day.

Most shops etc use battery testers to show that yours is faulty even if its not
You could turn some of the things off when driving first thing

 

[jtr]

JTR,what was the cost of the replacement battery?

The bill showed the unit price as £110 + VAT. (I did look in Halfords but my 2004 W211 wasn't listed in their battery catalogue.)