BMW E36 & E46 Alarm Siren opening up to change batteries - similarities between the 2 alarm modules!

[@TheSmarts-v8w]

Excellent, I've been looking for this video for weeks now. What does the batteries power on the siren? Back-up alarm power for the siren alarm noise or just the beeps to lock and unlock the car/alarm system

[@carsonstage4274]

@@TheSmarts-v8w The batteries power the Siren speaker thats it - there are videos on KZbin showing external battery pack mods which ive personally done on my Audi A4 however the BMW is in the engine bay so my advice if replacing the batteries replace like 4 like as it was originally. I hope this helps Thanks for the comment!

[@TheSmarts-v8w]

@@carsonstage4274 So the Siren Battery is the battery backup for the alarm and does not peep when setting the alarm then?

[@carsonstage4274]

@@TheSmarts-v8w you're absolutely on the money yes, the batteries are there to keep the siren sounding, So even if the vehicles 12v battery was disconnected the alarm would keep sounding. The chip board controls the rest, i beleive the beep on locking & unlocking can be programmed on or off but only on the later E46 as it is later OBD2 with a more sophisticated software over the E36. If the batteries have leaked acid or have failed due to age then again you won't get the beep. For the E46 there's a seller on eBay that makes a plug & play replacement for the bateries. Hope this has been a little more helpful Let me know if you need any further information and I'll try to help. 🙂