ziggy5875

hi, i am new to this forum
I have a C320 that has just been giving me nightmares since i've bought it. I love my car, she drives like a champ when she's running, but she's given me so many problems.

just this morning the car was parked in the garage and i hear this very loud, high pitch siren sound. I opened the hood of the car and it's definitely comming from under there somewhere. I disconnected the battery and the siren isn't quite as loud now but it hasn't stopped.

there is no power to the car, the doors are locked and i opened the door using the little key and there's no power, the key will not turn so i can't drive the car

The noise is comming from the passenger side wheel area, i pulled 3 fuses for the alarm to see if it was the alarm but the siren sound was still there. the fuses i pulled were 8,9, and 41.


any help would be GREATLY appreciated

acr2001

You don't even tell us what year you have.

When a car battery dies, usually the alarm goes off. This is pretty basic knowledge. You need to find out why the battery died. Did you leave the lights on? Might just be time for a new battery.

The siren sound is the alarm.

Did you even read the book for your car?

ziggy5875

Hi,
I appologise, it's a 2001 C320
the battery is new. The ignition switch went out last year and the battery was changed at the same time.

i've been doing some research and i've found out that the automatic seat actuators do go bad frequently on these cars. What i do not understand though is why when i've disconnected the battery this morning and the alarm siren is still sounding. Is there a separate battery for the alarm?

I also pulled the 3 fuses for the alarm system and the siren is still sounding.

ziggy5875

Okay, I have a little update.

I have pulled the fuses to the alarm system, beforehand there was no power at all going to the car (the instrument cluster wouldn't light up orange or show mileage etc..)

since i've pulled the fuses to the alarm, i reconnected the battery, i also had disconnected the actuators for the seats both drivers and passenger side. I then put the key in the ignition and there were lights in the cluster which is a good sign. I put the key in the ignition and now i am able to turn the key but still no start.

I went to check the voltage on the battery and it read 11.2V, so i'll charge the battery tomorrow and hopefully i can at least get the car to start.

the instrument cluster was reading some SOS sign and a tele something sign.

but hopefully I can get the car started

acr2001

Yes if the battery is new and there's no other reason why it would have died it is usually one of the seat modules. Unplugging them is the easiest way to find out. If you have a multimeter and know how, you might want to look at the current draw on the battery when the car is off and the systems are in sleep mode. I think it's supposed to be somewhere around 500mA max but that number is probably not right - search the forums for more info.

I do believe you have a backup battery for the alarm (I guess you've proved that!) but I really don't know much about that.

ziggy5875

yes, i'm confident that there's a backup battery for the alarm! There were 2 different sirens when i re-plugged up the battery. The one coming from the passenger wheel area and another one clearly for the alarm. As soon as i pulled the fuses for the alarm, the siren went off for the alarm. I just hope that there isn't an ignition cutoff that will prevent me from starting the car.

ziggy5875

Hi,

I have an update on the car.. I got the car started. By pulling all 3 fuses to the alarm system, it disabled the car so the ignition kill was disabled and i'm able to start the car. The keyless entry system still works which is interesting. This leads me to believe if i reconnect the fuses to the alarm i'll be able to disarm it with no problem. I just don't want to try it now because it's dark and i don't want to disturb my neighbors. I will try to disable the alarm tomorrow. The dome lights and climate control don't work, the reason being is after looking at the wiring of the car, they are linked to the alarm system fuse, so by pulling those i've also unintentionally dissarmed the dome lights and climate control. Everything else works perfectly fine, there's 1 malfunction on the car, i forgot what it was for and an SRS light which will need to be reset at the dealer.

other than that everything is great and at least i got the car running and can drive it now!

i thank you greatly for your help and i'll keep you posted on if i can fix the alarm and get the dome lights and climate control up and running again!

Moviela

The car alarm has no "back-up" battery. The siren is behind the lining of the front right wheel arch.

Seat modules failing to enter the sleep mode when the car is off causes a current drain that can discharge a battery overnight. It is a defect in the design, and I can't believe someone has not held the factory responsible for the replacement of the modules.

From the descriptions of this thread, it sounds like the car has an additional alarm installed. I am not sure why anyone would want an additional alarm, but some dealers like to pack the sale with expensive add-ons.

TemjinX2

my car made the same noise when my battery died from the seat control modules. It made a low buzzing sound even when i disconnected the battery.

When i recharged my battery and disconnected the seat control modules, the sound went away.

acr2001

I didn't believe we had a backup battery either, but do we? Something has to be causing the low buzzing sound! I doubt its power left in capacitors - usually they drain out pretty quick, a matter of seconds. I guess someone could confirm by disconnecting the neg battery cable and seeing if the alarm sounds, but I'm not trying it!

ziggy5875

im pretty sure there is a backup battery for the alarm because my mom's alarm kept buzzing after i pulled the battery!

billbugger

Out of context, that is hella funny!!!

ziggy5875

well guys i have an update on the car!

this car has given us soo many problems, it's been to the shop like 9 times since we've bought it new in 2000!

What i did is i took the battery, got it recharged, unplugged it from the car for a whole day, i unplugged the power seats, after a day, i reconnected all 3 of the srs fuses, replugged up the battery then the alarm syren started chirping as i replugged up the battery (please note this chirp was different than the one that came from the front fender area)

immediately i tried to disarm the alarm by pushing the lock and unlock buttons on the keypad but this did nothing. So i put the key in the ignition, the car started and the alarm shut itself off.

surprisingly, all of the SRS light, SOS, and the cluster reset themselves because now EVERYTHING works flawlessly! Even the cluster it said to "visit workshop", well now it says 0 malfunction!

I just wanted to thank you guys for your help you all saved me a lot of money! Everytime she goes into the dealership it costs over a grand!

TemjinX2

nice..just make sure you unplug the front harness of the seat control module if your modules are draining power.

SickSpeedMonte

I noticed a high pitched screech sound from my front left wheel yesterday when i was washing it. The car was off, key out, and every 30 seconds or so, I would hear this sound for about a second and then it would stop. It wasn't loud. This is on a '07 C230 SS by the way.

SickSpeedMonte

TTT
heard it again yesterday. It doesnt seem to drain the battery, but I never really go more than 36 hours without driving it.

Glyn M Ruck

There is a backup battery on my car but the South African models have a more sophisticated, but still genuine, alarm system which locks the transmission so you have to pick the car up to steal it.

acr2001

You get all the good stuff over there!
I have to ask, what's the difference between the alarm system locking up the transmission VS having an automatic transmission in park? Doesn't that accomplish the same thing? I would think with a 4matic in park all 4 wheels are locked...

Back to the battery, I hear in a lot of posts on the W203 forum about the alarm going off without the battery in the car, but in other posts I hear that the W203 (US anyway) does not have a backup battery for the alarm. I really don't know who to believe. I would pull my neg. battery cable and try it, but it's too risky with our electronics, I'll wind up with a warranty claim.

Moviela

Hi Glyn, I looked at the EPC, and I can't find a battery listed except the SLI and key batteries. Where is it on your car? If you have located a battery that is it roughly 100 x 300 x 25 mm, that would be a backup for a Tracker vehicle recovery device, they are the SA peddler of Lojack.

The only difference I see between the SA and American alarms is the radio frequency. They both are connected to the front SAM and immobilize the engine and transmission. They also have an input for an interior motion sensor.

You say pick the car up to steal it? Ha! I know some fellas in Irene that could steal the **** out of a wart hog without him knowing it was missing. They would drag your car away if they needed it in 10 seconds.

SickSpeedMonte

I wonder if we might be on different pages here. The noise that I am hearing is not loud enough to ward off any criminals, by a long shot. It sounds like an electronic component operating... maybe like a linear actuator or a small electric motor. I guess its like a cross between a buzzing and a squeeling. When I washed the car, it would do it once every minute or so, and it would last about 2 seconds. I could hear it best by listening by the front left wheel (LHD US car). This was with the ignition switch and all accessories off, and the key in my pocket.

Glyn M Ruck

Hi Moviela - I sometimes think you are clairvoyant. I have to say I'm making my comments on trust of MBSA & my service manager. My car has a Tracker fitted. I watched that being installed to ensure no damage to a brand new car by some monkey so I know that entire system. When it comes to the alarm system - MBSA & my service manager maintain that this is the only market in the world that has this version of the MB alarm system fitted & that it has a backup battery & it's listed as a serviceable item. I don't know where it is but I will find out.

To address comments by yourself & acr2001 - MBSA maintain that the standard gear lever interlock is easily defeated to unlock the Park pin. The SA version without a key is apparently hell to defeat. Even Tracker maintain this. If this is all BS I would be very surprised. It's too easy to check out. We are the crime centre of the world although South Dallas & Sao Paulo make me wonder. The EPC is not infallible - these cars are not uniform globally. I agree a determined thief will easily steal the car but Benz has earned a reputation here as a ***** to steal so they steal BMWs

acr - to address your comment that we get all the good stuff here - Our cars are more highly spec'ed standard here with standard full leather etc etc but we pay a hell of a lot more for them than you do & we make them here. Benz have to compete with Lexus & the likes that hit this market fully loaded (as does AMG) - no options apart from body colours & colour of leather. Lexus even fit reverse cameras on base IS250s here as Toyota do on SUVs. Another thing to remember is that Benz have a model called the Classic here which is more basic but does not sell well. Elegance & Avantgarde have always been very well appointed & are even more so in the case of the W204. I'm surprised at the American 204 spec but look at the low sticker price!!! Why things like Parktronic & Distronic were not offered on the 203 in the US - who knows? I'm told that my BiX front bumper with clear fogs was not offered in the US or Canada - is this correct? and we've never had those tee shaped door pins here - ours are fluted.

acr2001

Interesting stuff. You don't happen to have a photo of the door pins do you? I'm interested to see the difference.

I know the 07 W203 (and the W204?) in the US has really cheap door pins: http://i253.photobucket.com/albums/h...g?t=1236994405

The previous years had at least some chrome in them- my 05 for example: http://i253.photobucket.com/albums/h...g?t=1236994473

As long as I'm posting comparisons, another interesting bit is the 07+? light panel: http://s253.photobucket.com/albums/h...t=PICT2218.jpg which is black no matter what color your interior happens to be.

Compared to the earlier lighting panel (my 05 again):
http://i253.photobucket.com/albums/h...g?t=1236994578

They really seem to cheap out over the years! I took these photos when we had a 2007 loaner side by side with my 05. There were other differences too like the new fog lights which were a step back, lack of satellite or telephone pre-wiring, no upper compartment in the center console, sunroof no longer standard for the US market... the list goes on.

BTW Glyn, your steering wheel seems to be on the wrong side

Glyn M Ruck

Our lock pins are similar to the top picture - just plain black fluted - They consider them lock indicators here. The light switch panel remained colour coordinated here. I will shoot a pic for you - that's easy

All prewiring remained in this market.

I'll report the steering wheel at my next service

Glyn M Ruck

Coordinated light switch





South African full leather seat





Door lock pins

Glyn M Ruck