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Warning light keeps flashing after locked, and fuse #5

12094 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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Unplugging the alarm did not help for me. The lights would still flash randomly and drain the battery.

I replaced the siren unit and all was well for a couple of days, until my neighbour complained the alarm was going off in the night.

Had the car diagnosed on STAR and discovered one of the alarm sensors was faulty. They disabled it on STAR and there has been no problem since.
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