Which factory alarms are plug'n'play

[Dan in NZ]

I want to get the factory alarm, just so I have keyless entry. I'm not too worried about security because it's pretty safe around here, but keyless entry would be handy. I want the factory one so I can just plug it straight in with no worries. I have a 11/89 buil 525i, and I found a green plug near the fusebox under the back seat that I assume is for the keyless module. When looking through the wreckers, which cars have a compatible units??? Are all E34 alarms compatible, how about E32?

[Rick L]

I’ve seen two different harness types for E34. Both were OEM BMW by Alpine but more connectors in harness for newer Alpine alarms (newer E34). You should check the connector type first as they look completely different.

Picture below is the OLDER harness type for E34 and E32. My 1995 E34 harness looks nothing like this one.

[Derek A.]

Was there something available for 88-92 ? Everything I have seen is for 92 and later cars. On an FAQ someone mentioned hacking into the driver's footwell, is this correct ? Is it a plug ? bare wires ?

[Dan in NZ]

I had my RHD Drivers side underneath-of-dash apart a while back, and that connector looks familiar. There were quite a few blank connectors in there, I'm sure one looked like that. The text mentions that sometimes the connector is the passengers footwell, perhaps on RHD cars it's the drivers one???

Last time I was under the back seat there was a green connector with a small plastic bag over the end. It had more than 12 pins though, looked like a computer data cable or something. Wonder what that's for...