Originally Posted by
Robertwav1
Well finally got around to taking the siren apart again, sealed it really well so took a little time. One of the batteries I purchased is completely dead. The board looks good so I may just throw another battery in it. One of the batteries read 3.7 Volts, the other .128 volts. I wouldn't suppose the board would have fried the battery, I think it was just defective?
If you use eBay often type in the new part # for the alarm and save the search. I’ve come across practically brand new ones for 35$ and up. With production dates being 2016 and up. They’re used in so many Mercedes models that when the cars are scrapped the alarm is basically new. Just a thought if you get tired of changing the batteries. Plus the newer alarms have a beeping chime which is a bonus IMO.