2006 S211 red battery warning

[lrochfort]

Hello all,

I have a 2006 E280 diesel S211.

A couple of times recently I've received a red battery warning on the dash. There's no other information, just the red battery icon. The car starts and runs just fine. I'm mostly doing short journeys, but have done a couple of 40 minutes drives lately.

I measured the battery with the car off, and it's showing 12.3v.

The battery is a Mercedes Benz Varta branded battery. I've only had the car for a few months, so have no idea when the battery was changed.

I've attached a picture of the battery. Does anybody know how to read the numbers on the top to determine the age?

What do people think, should I replace the battery or is there some other issue at play?

 

[KillerHERTZ]

Its likely thats the orignal battery and on its last legs.

 

[ToeKnee]

I believe the age is stamped on one of the negative/ positive posts as month/ year.

 

[DSM10000]

I believe the age is stamped on one of the negative/ positive posts as month/ year.

As above..

Before changing the battery check the voltage with the engine running to rule out an alternator issue.

The short journeys will certainly take a toll on battery capacity, each time the glow plugs are used you are drawing 30 Amps x 6.

Also a 40 minute drive is not going to replace all of the lost charge capacity. You could try charging the battery and checking it again.

Also check for parasitic current draw when everything is shut down. The W211 is known for issues in this area according to my Independent.

 

[Teego]

Good fast fits like Formula 1 Autocentres do free battery checks.

 

[Azeem]

Does your car has SBC, I know that SBC was discontinued post 2005 but yours could be late 2005 or early 2006? If yes, check the auxiliary battery under the bonnet (just below the AC filter).

 

[Azeem]

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[bolidemichael]

The voltage can be checked with a sequence of presses on the binnacle reset button. Three in swift succession iirc

 

[Gbrowncls55]

Just interetsed . Do 211s without SBC (ie post 2006 ish) not have an aux battery in the front. I thought it was for more than just SBC

 

[DSM10000]

Face-lift W211 models from 2006 do not have an Auxiliary battery

 

[Gbrowncls55]

Every day is a school day. Thanks

 

[millo777]

The age of the battery is entirely irrelevant. You need to get the battery tested properly to see whether it will hold charge and how many cold cranking amps it's still putting out. Places like Halfords or kwik-fit will test the battery for you free of charge, but make sure it's properly charged when it's tested or you'll get an inaccurate result.

If your w211 has memory seats, I'd place a bet they are causing a parasitic current draw. I had a whole world of strange electrical issues with my w211, all of which were due to constant low voltage conditions due tot he memory seat modules draining the battery. There is an easy fix to this problem which you'll find if you google it. It involves cutting the constant power supply to the seat module and splicing it with the switched power supply wire.