Red battery warning light on

Moulari

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SL 350 2006
Hello
My car is an SL 350 2009 facelift
I really need your help
I switched on the engine last week with a red warning light with a battery inside “no other messages like visit worksop “
Though was a bad battery so I charge them both with a ctek 5.0 and connect them back the right way ( starter first and then boot battery last.
Switch on the engine and Red light pop up!!!
Next step is to check alternator
I check volt on start battery and when engine is off is 13.3volt and goes up to 14.3 when engine runs so alternator I think is working properly
I scan for codes with a cheap obd2 but no codes comes up
Anyone have the same problem or can give me an advice what to check next ??
CE8553C7-2E05-486A-94D2-7A922E5C113B.jpeg
 

Stafford71

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W208 320 Elegance
Bad earth maybe. Are battery terminal connections clean etc

Sent from my ONEPLUS A6003 using Tapatalk
 

Janchee

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W213/2016/220D 190
Hello
My car is an SL 350 2009 facelift
I really need your help
I switched on the engine last week with a red warning light with a battery inside “no other messages like visit worksop “
Though was a bad battery so I charge them both with a ctek 5.0 and connect them back the right way ( starter first and then boot battery last.
Switch on the engine and Red light pop up!!!
Next step is to check alternator
I check volt on start battery and when engine is off is 13.3volt and goes up to 14.3 when engine runs so alternator I think is working properly
I scan for codes with a cheap obd2 but no codes comes up
Anyone have the same problem or can give me an advice what to check next ??
View attachment 65856
What setting did you charge it on for battery? (On the CTEK MXS 5.0)
 

sonic

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E350CDI, SLC250d, FJR 1300
I would disconnect the battery for half an hour & try again. Does the car start?
 
OP
M

Moulari

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SL 350 2006
  • Thread Starter
  • Thread starter
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I would disconnect the battery for half an hour & try again. Does the car start?
Everything works fine just a warning light tat is on
 

sonic

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Everything works fine just a warning light tat is on
Sorry should have read it more carefully, I think I would continue to drive it & see what happens next.
The only other option is to pay & have it put on Star.
 

SL55 Mark

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2004 SL55 AMG
Did you charge the front or the rear battery ? You are only supposed to charge the rear.

How old is the battery ? It should be an MB AGM one. The date codes are on the terminals. It could be new battery time.
 

John Laidlaw

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BMW 530d X Drive Tourer M Sports
At the end of the day you can’t give condition to an expired battery...
£200? Why flog it !
 

John Laidlaw

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Battery is healthy and one year old
Apologies, I got your post mixed with another one on the same subject! Old age I guess....the other poster's battery was 6 years old hence the comment :rolleyes:
 


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