Disconnecting Car Battery in E36 95 coupe

[Brad-325i 2]

Hey now im about to attempt to take the cd player that was origionaly in my car out and chuck in an amp and sub. now before i disconnect the battery terminals is there anything i should know?? Anything i should do b4hand?

Cheers,

Brad

[hotwire 352]

Nup, just disconnect neg terminal on battery

[Brad-325i 2]

Nup, just disconnect neg terminal on battery

When i do that my alarm goes off but sounds like its bout to die haha and i lost the key to turn the siren off so shuld i jst let it go till it dies? if i connect the neg terminal again the alarm works perfectly fine again.

[_ethrty-Andy_ 2136]

When i do that my alarm goes off but sounds like its bout to die haha and i lost the key to turn the siren off so shuld i jst let it go till it dies? if i connect the neg terminal again the alarm works perfectly fine again.

Its probably got a backup battery in it for when the car is locked for extended periods of time. its often a 9V battery. see if you can see an access panel for it

[*Glenn* 855]

Just put a rag inside the siren to quieten it down and let the back up battery go flat after you disconnect the main battery... it wont hurt it

[Brad-325i 2]

Just put a rag inside the siren to quieten it down and let the back up battery go flat after you disconnect the main battery... it wont hurt it

how long will it take to go flat? i have neighbours that complain about every little sound i make.

[*Glenn* 855]

Not long .. a few minutes

[summerscheifer 0]

i know its was a year old one but im just having the problem on my bmw battery when i switch in the battery one,it make quick tick sound from relay in motor,but when i switch to battery two or both it will start right up,is the relay bad?or i need to check something else?or should i have a battery switch for that?please give me some tips. thanks.