bmackay

Hi all,

My car has been sitting for about 2 months and the battery was dead. When i went to go jump the car - the alarm siren would not shut off. What i had to do was pull the fuse out, but when i take the fuse out it also disables my power locks and power trunk. Does anybody know why the alarm wont turn off? and if in fact the siren fuse is connected to the power locks/trunk? thanks very much for the help.

bmackay

over 40 views and 2 days and not a shred of help? nobodys has had a alarm issue when jumping their car?

aqua190

only thing that comes to mind is maybe the battery is so low, that even after jumping, the voltage is making the alarm go off. sometimes low batteries can make veh do strange things....i've seen vehicles jumped and then the tach not work, or guages erratic while they're running. then a new battery and everything is back to normal.....hope it helps.

falls profet

This could be the answer, although which fuse are you pulling out; number wise?

Also, if you lock then unlock (or vice versa) the car, it should turn off. This worked for me when I had to change my fuse for my rear dome light.

Staples6

My s430 is doing this after the battery died. Alarm won't turn off I've tried the fob, the key everything!

Serndipity

Have you tried disconnecting the battery (e.g. just need to disconnect the negative terminal)?

Actually, there is some science/logic this.

Even when your car is turned off, several critical components (e.g. obviously the alarm system being one), always remain connected to the battery. There are various sensor inputs to the alarm controller, connected through the CAN-Bus, which works via voltage encoding. The way voltage encoding works, is that electrical currents, flow to vehicle ground trough the various switches and or sensors. The voltage has different values, corresponding the circuit's current flow and/or resistance (e.g. OHM's law, where voltage = current x resistance). If the voltage level is incorrect, due to resistance (e.g. a faulty sensor or switch) or the battery condition, you will have a system error/malfunction.

Having let your battery run down, yet with still enough voltage remaining to keep the alarm controller active, may have triggered a faulty input sensor signal, which without a reset remains.

Disconnecting the battery's negative cable will remove 100% of the voltage to the vehicle and hopefully reset (i.e. erase) the condition triggering your alarm.

It's like chicken soup......it won't do any harm and may do some good.

Note: After removing the battery via disconnecting the negative cable, you'll have to reset the usual radio code, ABS/BAS warning and power windows, which is explained in your owner's manual.

dlbehrns

FWIW: put the fuse back in, hock up a battery charger to the cables in the trunk(or under the hood) at no more than 2 amps before you replace the old battery and and see what happens. When my original battery(99)finally went south after 15 years, which I think is pretty awesome, there was not enough juice to turn the car over but enough to light interior lights etc.,(and in your case run the alarm)so as long as you keep the ECU live you won't have to go through the whole reset hooie/procedure. FWIW

beefstallionAMG

Have you tried a trickle charger?

-Disconnect battery
-Inspect batter - pop off lid and check water levels. If applicable add water to marked level
-Re connect battery
-Connect trickle charger purchased at Harbor Freight etc
-If this works go through re-set procedure
If you have continued problems call MB usa for battery replacement.
MB offers free assistance as long as you own your car. I haven't used it recently. It used to have an amazing reputation but recently has been getting mixed reviews.

http://mercedes-benz.custhelp.com/app/call

beefstallionAMG

Try calling 1-800-FOR-MERC and see what complimentary work they will do for you. http://www.starmercedes.com/roadside.htm





Try calling1-800-FOR-MERCEDESS