gwaters

Hello, I have a 1997 E320. Last week at night the alarm started randomly going off. I took out the battery to trickle charge it back to full strength but now whenever I reconnect the battery the alarm goes off and when I try to start the car the entire thing goes dead. I need to sell the car this week to cover an emergency so I'm praying someone knows an easy fix to reset the alarm or how to disengage it. Thank you so much!

raymond g-

i don't know and only have more questions:

check under the rear seat where there is a cluster of valuable targets critical to the operation of
your car (relays, fuses, car battery, vacuum pump). see if there ANY indication of moisture be
it moist, wet, water marks on the sponge or insulation

the thinking here is that water might have entered and shorted out something (clogged roof or
door gutter)

why not disconnect the battery again? wait a few minutes. tap the NEG and POS leads together
to discharge any resident voltage in the car (stay clearly away from the battery). then reconnect.
see if this easy attempt resolves the electrical gremlins causing the anti-theft symptom

there is an anti-theft rocker switch on the console. while the alarm is going off, did you try pressing
the switch?

are the exterior lights flashing in sync with the siren?

does your remote key have a PANIC button to turn off/on the siren?

the tilt sensor is near the car battery but I don't recall if it is also in the well, or frame exterior

the siren is under the right/passenger side wheel well liner. size of a grapefruit. even if you remove it,
the lights may still flash...and the anti-theft disabling feature might continue

gwaters

Thanks for getting back to me. I had the battery disconnected overnight, touched the positive and negative cables before reconnecting the battery and the alarm immediately started again once I connected the negative cable.

My remote doesn't have a panic button but I hit the lock and unlock button on the remote while the alarm was going off and hit the console lock/unlock buttons to no effect. The lights weren't flashing though when the alarm was going off.

I couldn't find any standing water in the car. Is there an alarm fuse by any chance I could pull so at least the siren won't go off so I can try some other things?Thanks

khomer2

Look in your fuse box under the hood. Fuse #41 (anti-theft)? I recall for w210s

raymond g-

coincidentally, on another w210 forum....

https://www.benzworld.org/forums/w21...ckout-won.html

bbirdwell

The alarm has its own internal battery (in case the thieves cut the battery cable to kill power to the car). When this internal battery goes bad, the alarm will sound intermittently. The entire alarm has to be replaced IIRC. So, find the alarm (likely under the fender liner) and remove or replace it.

Pull a search on "w210 alarm module location" and you'll find plenty of information.