JASMINx93

Hi,
I came home today and the battery on my Mercedes C320 is dead - nothing inside the car works, the smartkey won't work, it won't budge in the ignition and/or unlock the doors. Also, none of the interior lights or buttons work whatsoever. When I press on the brake, brakelights do not come on, etc. etc.
Anyways, there is also a really weird loud repetitive noise coming from underneath the car.
Does anyone know what it could be?
thanks!

Dingleberry

this might come to you as a surprise, but your battery is dead.

also search.

hanknum

Yep, dead battery and most likely some sort of drain (check seat modules). Charge it up and find out where the drain is.

JASMINx93

Well I know the batteries dead, but why is the repetitive noise coming from underneath the car? Is it an alarm that comes on when the battery dies or something? It sounds like a siren/alarm, but not like a regular car alarm.

bdgdl08

There are alarm issues when the battery goes. FYI, you can't jump your car. I'd call the 800 number and get the MB people to come out and get you going.

03MBC320

^^ why cant he jump it? (i have the same model, so thatd mean future reference i wouldnt be able to jump mine... which is something i'd normally do if it didnt start haha)

BigBodyBenzC240

If you jump your car you run the risk of blowing up/frying your rear SAM. The battery needs to be replaced or trickle charged back to the correct voltage.

bdgdl08

MB Roadside's still easier. All the liability is on them, and it's free!

samaritrey

+1 that is why i had them replace my battery if they blow the sam i will not be as i walk to work for a month till i can fix my car lol