Red battery warning symbol - new battery fitted - help!

[majoreyeswater]

Yesterday, i got the red battery symbol on the dash, Ive checked the standing voltage and was 12.4v, alternator seems to be doing the job - putting out around 14.4v.

So this morning i picked up a new battery, pulled away from the shop and the symbol came back on...

I disconnected the new battery for an hour then reconnected and started the car - the symbol came back...

Where do i go with this guys?!

 

[Stratman]

Straight to an auto electrician. Preferably one with a decent code reader.

 

[Gbrowncls55]

cant see what year your car is. Does it have an Aux battery under the bonnet as when my red battery light came on it was that battery and not the main consumer battery in the rear. Mycar still had the original aux battery dated 2005 (in 2018)

 

[johnsco]

Check out post #3.
This may be the problem.
But
As this is a new battery - You don't know its state of charge.
The car is obviously starting and running OK.
This does not mean that the new battery is fully-charged.
[One cell may be quite low]
I would put it on my battery charger and leave it on over-night.
I would then drive the car for a couple of days.
If the red light keeps coming on - Then -
I would either do further fault-finding
or
I would go to an auto-electrician.

 

[majoreyeswater]

Thanks all.
It's a.2011 e350, will that have an aux battery?

 

[Gbrowncls55]

I don't have a 212, but from what I can see, yes it does. A quick look in the owners manual should clarify. Or someone else on here can confirm

 

[AMGeed]

Thanks all.
It's a.2011 e350, will that have an aux battery?

Do you have stop/start?
If so, the aux battery will be in the spare wheel well on the offside under the boot carpet.

 

[190]

But
As this is a new battery - You don't know its state of charge.
The car is obviously starting and running OK.
This does not mean that the new battery is fully-charged.
[One cell may be quite low]
I would put it on my battery charger and leave it on over-night.

This above.

The first thing everyone should do with a new battery is fully charge it before installing in the car. If the 12.4 volts was measured before being installed in the car then it was only 50% charged. and really would need an overnight or perhaps a full 24 hours charge to bring it up to full charge. If 12.4 volts was measured connected to the car then it's anybodies guess what the state of charge was depending on how it was measured and whether the car was asleep.

 

[markjay]

Isn't the battery symbol an indication of a problem with the charging circuit (e.g. alternator etc)? I don't think that on a 2011 car there will be any particular indication for low battery voltage as such. Are you able to get the fault codes read using STAR or iCarsoft/Carly?

 

[johnsco]

The OP's post #1 suggests that the alternator is charging.
As said earlier - The first thing to do is to make sure that the battery is fully charged.
If the red light stays on after it has been run for a couple of days, then there is clearly another fault.
The alternator / charging circuit ... OR ... the auxiliary battery are possibilities.

 

[majoreyeswater]

I've got an auto spark coming out next week, I'll keep ya posted

 

[Bobby Dazzler]

I think you might need to a low voltage error code deleted using STAR (Mercedes diagnostics equipment) or similar.

 

[Fez7]

This light popped up on the wife's Focus about 6 months ago. When she took the car out the next morning the auxiliary belt snapped a short distance later. Lesson learned the hard way... Red light means do not drive!