New 2002 SL500 owner

[Richard Willetts]

Hi everyone..just bought my first mercedes and bought a low mileage..full service history in mint condition SL500.
It's a 2002 5L V8 In amber red..

But I've got alarm issues..only happened since battery in boot needed replacing..
So when you get out of car and lock it from the key fob the alarm goes off straight away and it does this every time...
Any suggestions please..

Thanks

Rich

 

[LostKiwi]

Hi and welcome. Great choice if car.
You may need to put it on Star to determine what is causing it to trip.

 

[Blobcat]

Hello and welcome

You’re in the right place with an early R230 SL500...

 

[Richard Willetts]

Is star only available at mercedes or can a local garage diagnose the problem

 

[Blobcat]

There’s some very good Mercedes indies on this forum with star diagnostics. I wouldn’t be taking an 02 SL anywhere near a Mercedes dealer

 

[LostKiwi]

Is star only available at mercedes or can a local garage diagnose the problem

Dealers have Star but so do most MB independents and some members (me included).
If you tell us your general area we can probably suggest someone.

 

[Richard Willetts]

I'm near Sheffield South Yorkshire..

 

[John Laidlaw]

https://www.rhautoservices.co.uk/
Richard knows his way around SLs and can replace bottom ball joints on the ABC struts too

 

[Craiglxviii]

Hello and welcome. What a lovely colour that car is.

 

[Richard Willetts]

From what I've been told..quite a rare colour in this model..

 

[gramey]

So this may seem like a stupid question but when you replaced the consumer battery in the boot did you full charge it, they don't come fully charged, as in on a decent charger that will show you what capacity it's at, a fully charged 12v battery should sit at around 14.8v.
I ask this as low voltage on the consumer battery can cause various electrical gremlins, I replaced mine but the battery still kept discharging because certain systems weren't shutting down due to low voltage. It may be that the alarm is activating if the voltage is low it thinks the battery has been cut? I know when I fully charged mine new battery the problems disappeared, that was a year ago and haven't had a problem since, just a thought, good luck and I hope you find the cause.
Nice colour car although personally not a fan of the wheels, I had the same 'drug dealer' style wheels on my previous R129 but changed but it's each to their own on such things.

 

[Tony Dyson]

I would suggest that 14.8v is a charging voltage and you should be reading between 12.1-12.6v maximum from a healthy standing battery.

 

[LostKiwi]

I would suggest that 14.8v is a charging voltage and you should be reading between 12.1-12.6v maximum from a healthy standing battery.

12.4 to 12.8 is normal resting voltage. Any less than 12.4 and the battery is beyond its best.

 

[Richard Willetts]

Thanks for all the advice..going to check the battery today

 

[Richard Willetts]

Agree about the wheels..but the previous owner gave me the original 16" alloys as part of sale so will get swooped at some point

 

[LostKiwi]

Simplest thing to do is put the rear battery on charge and see if it still does the same.

 

[Richard Willetts]

Just checked battery and it's reading 12.6v..

 

[gramey]

Just checked battery and it's reading 12.6v..

Ah ok that sounds as if that's fine, sorry for the early spurious figure I quoted, should be 2.1 volts per cell so 6 cell at 12.6 volts is spot on, is the problem persisting?
As for the wheels 16's sound small for the originals more likely 17's or 18's but others will know better, mines on 18" Mercedes wheels and I think they're a good compromise between ride and looks.

 

[Richard Willetts]

Yes still happening..been on star today and it's reading a fault of B1076 rear sam..checked as I've been told could be full of water but dry as a bone..

 

[LostKiwi]

Agreed 16s sound too small (r129 sized).