E89 SD35IS Alarm Issues

Justjeff1972

Member
 Nebraska
Good afternoon to the brain trust. I've started to have an issue with the alarm on my 2012 E89. The alarm goes off without anyone molesting the car. Sometimes it works fine but then, this morning, it went off three times before I got to the door to my office building so I turned around and left the car unlocked so I didn't have to worry about coming back to a dead battery. I know the E85s/86s have hood sensor issues. Does that plague the E89 also? Is there a way to see what sensor is causing the alarm either in the car's system menu or using Protool? Is there a way to lock the door without setting the alarm or does it have to be disabled in the programming? I don't want it going off incessantly causing the battery to drain or annoying other people. That alarm siren really carries! Thanks.
 
If it's a 2012 MY on the original battery trust me its the battery causing the alarm issue - change the battery and the issue will not persist 👍
 
If it's a 2012 MY on the original battery trust me its the battery causing the alarm issue - change the battery and the issue will not persist 👍
I know for sure it isn't the original battery because it's a die hard. Just not sure when it was last replaced. I'll look to see if it has a date code.
 
I know for sure it isn't the original battery because it's a die hard. Just not sure when it was last replaced. I'll look to see if it has a date code.
Apologies I had misinterpreted your original response assuming it was still the original BMW battery.

Not sure how it works in Nebraska but here in the UK most car battery retailers offer a free battery health check. If the option exists I'd go down that route and have it tested first 👍
 
My sister in law has an e92 - same electronic system as the e89. Her alarm sensor for the bonnet/hood is unplugged, so I assume a previous owner had problems. It looks the same as the one on my e86 and old E46, so I'd try unplugging it.

After all, it's easy and free to diagnose. Good luck!
 
Apologies I had misinterpreted your original response assuming it was still the original BMW battery.

Not sure how it works in Nebraska but here in the UK most car battery retailers offer a free battery health check. If the option exists I'd go down that route and have it tested first 👍
I can swing by the local Auto Zone or Batteries Plus and have them test.
My sister in law has an e92 - same electronic system as the e89. Her alarm sensor for the bonnet/hood is unplugged, so I assume a previous owner had problems. It looks the same as the one on my e86 and old E46, so I'd try unplugging it.

After all, it's easy and free to diagnose. Good luck!
I'll take a look at it later. I'm not really that concerned with someone trying to get under the hood around here. I would like to keep the cabin sensor though for when the top is down and it's parked. That is a pretty slick feature.
 
You can with obd read historical charge data. It might start the car well, but might only be say 40% capacity, so just a voltage check under load won't show much.
Make sure you have nothing metallic behind seats.
I once but scissor jack behind seat and it set off the alarm, until i removed it.
 
Got to agree after quite a lot of years with a z4, and seeing hundreds of similar threads.

Weird electrical issue? It's always the battery at the top of the suspect list.

These cars (like many) are chocablock with electrical systems that throw a fit if the battery is not in good health.

Being able to start the car is not a test - various electrical components will be unreliable way before you see starting issues.

Life of a battery in these cars is rated as 3-5 years, best to treat as a cheap maintenance item.

These are not your dad's Allegro :)
 
Back
Top Bottom