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Warning light keeps flashing after locked, and fuse #5

12101 Views 9 Replies 4 Participants Last post by  W208 Hawkwind

Sometimes, after locking the car with pressing Lock on the key fob, the orange lights flash three times (as it should), then keeps flashing very fast, and the interior lights stay on, as if the alarm just set off and no siren sound.

I found that, if I pull the fuse #5 in the fuse box that's located in the back of the trunk, it will disable it from happening. However, the red light on the truck button inside the car stays on, and no flashing three times at all when locking. It just locks the car.

I did a few research, it seems the problem is the battery inside the siren need replacing. Where is it located on a Right-Hand-Drive (UK/Japan specs) car? Do I need to replace the whole siren or I can just replace the battery?

Also, if I leave fuse #5 pulled, will it drain the car battery with the red light stays on all the time? And any other side effects?

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I've seen this on my wifes C Class, I unplugged the siren and problem was gone, it just means there is no sound when the alarm goes off. I keep meaning to buy a used siren off ebay.
Thanks. Do you know where is the siren located on a Right Hand Drive/Japan-spec car? Under the Driver side or passenger's side?

So, just unplugging the siren will fix it? Any side effects besides no alarm sound?
I found it and disconnected the siren; it's been a few days now, seems to have solved the problem.

What I don't understand is, since "disconnecting the siren" is equal to "having dead battery in the siren", why would it solve the problem... Maybe the flashing light is a warning that the battery inside the siren is low, not dead?

Anyway, hope disconnecting the siren will truly solve the problem. Time will tell.
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