Red Battery Light

[i PRIEST]

Getting red battery light on dashboard "Visit Workshop",, Changed both batteries but still comes on start up, goes off when you press steering wheel menu..
Any help would be appreciated

 

[ajlsl600]

Did u check alt charge rate? Maybe u have a suspect regulator. Goes off when u press steering menu? Till next start then comes back?

 

[i PRIEST]

Yes goes off when you press steering wheel menu, when start up it comes back

 

[mioba]

You need to get a voltmeter across the battery with and without engine running.

You could have changed the batteries when they were fine.

 

[AMGeed]

Sounds like the alternator is toast.

 

[i PRIEST]

Both batteries are new, but I will change alternator tommorow then see what happens...

 

[mioba]

A regulator is much cheaper and easier than replacing the alty.

 

[Misterdog]

A regulator is much cheaper and easier than replacing the alty.

A multimeter is cheaper than all three. ( four if you include the Aux battery )

https://www.ebay.co.uk/itm/234187971176?hash=item3686b0da68:g:fLUAAOSwH4lhPkeo

 

[Craiglxviii]

Multimeter… £5
Reg pack… £70
Alternator… £280
Both batteries… £250
Listening to advice first… priceless

 

[peterws1957]

^ This exactly. It's amazing how owners will spend hundreds of quid at guessing the problem. My local indie charges £45 for diagnosis (sometimes free) - saves a fortune that does.

 

[i PRIEST]

Well to be honest I bought the car in Febuary 2019, apart from servicing (oil change, filters etc) I have not spent any money on her, the rear battery packed up in April this year and has been replaced with a new one, everything was disconnected and reconnected according to the book, but the red battery workshop light remained on, so changed the front battery and still the red battery workshop light remained on,, So now changing the alternator and keeping fingers crossed.. The thing is you can't own a car like a Mercedes SL and dont expect to spend a little money from time to time, at least I have peace of mind for the next 3 winters as both batteries are new and alternator is new.

 

[Tony Dyson]

So is everything fixed now or are you still crossing your fingers that you've resolved your issues with the full alternator change?

 

[i PRIEST]

Well to be honest I bought the car in Febuary 2019, apart from servicing (oil change, filters etc) I have not spent any money on her, the rear battery packed up in April this year and has been replaced with a new one, everything was disconnected and reconnected according to the book, but the red battery workshop light remained on, so changed the front battery and still the red battery workshop light remained on,, So now changing the alternator and keeping fingers crossed.. The thing is you can't own a car like a Mercedes SL and dont expect to spend a little money from time to time, at least I have peace of mind for the next 3 winters as both batteries are new and alternator is new.

Again i dont know when the Alternator was last changed,, I could change the Alternator Regulator and 3 months time the Alternator packs up,, so it's better to spend an extra £70 and buy the whole unit for peace of mind..

 

[i PRIEST]

So is everything fixed now or are you still crossing your fingers that you've resolved your issues with the full alternator change?

Haven't heard from the gararge yet, dropped car off at 8am this morning,, should hear by 12 midday, so yes fingers still crossed..

 

[i PRIEST]

Haven't heard from the gararge yet, dropped car off at 8am this morning,, should hear by 12 midday, so yes fingers still crossed..

BINGO! New alternator has done the trick, red battery workshop light has gone, Alternator cost £210 with £72 return if you bring back the old one,,, so in theory I paid £142 which is not bad for a car of this calibre.

 

[mioba]

I do hope you got a genuine MB alternator.
ECP, GSF parts are getting worse.

Owning an SL needs money the "right" money spending in it, actualky as does anything.

Buy once buy right. Its not often the alternator itself fails but a reg pack.

Also not sure what batteries you got but Merc batteries lasting 8 odd years is not uncommon.

Aside. Glad you are sorted and motoring nicely.

 

[i PRIEST]

I do hope you got a genuine MB alternator.
ECP, GSF parts are getting worse.

Owning an SL needs money the "right" money spending in it, actualky as does anything.

Buy once buy right. Its not often the alternator itself fails but a reg pack.

Also not sure what batteries you got but Merc batteries lasting 8 odd years is not uncommon.

Aside. Glad you are sorted and motoring nicely.

The alternator is not an MB part it's a pattern, but hey we are in a world crisis with covid, we have to keep going somehow... No Way would I get an MB alternator for £210,, but what I got will do the job for now until I get an MB one as I rarely drive her maybe just once a month..
Thanks For All Your Inputs On This Matter Guys.. Great Help..

 

[Misterdog]

I rarely drive her maybe just once a month..

Which might make the new batteries only last a year, a voltmeter would enable you to check....

If a battery drops below 12V 3 times it knackers it.

A smart charger might also help.

 

[i PRIEST]

Thanks MD