Welcome to Bimmerfest -- The #1 Online Community for BMW related information! Please enjoy the discussion forums below and share your experiences with the 200,000 current, new and past BMW owners. The forums are broken out by car model and into other special interest sections such as BMW European Delivery and a special forum to voice your questions to the many BMW dealers on the site to assist our members!

Please follow the links below to help get you started!

Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 5 Series > 5 Series DIY

5 Series DIY
Knowledge Is Power! ~ The place for do-it-yourself threads on a variety of topics. Start a thread describing a particular job (oil change, cooling system overhaul, brakes, shocks and springs, etc.) or search for one you need help with!

Thread Tools Display Modes
Old 04-05-2005, 03:08 PM
mcg mcg is offline
Registered User
Location: Connecticut
Join Date: Mar 2005
Posts: 15
Mein Auto: 530i
Alarm sounds on disconnect

Today I had a battery disconnect switch installed. (See my post on Battery Disconnects, below). I chose the keyed switch from Flaming River. It is about as big as a soda can, very solid and well made. I had it installed to interrupt the battery's ground lead, thus disconnecting the battery.

The idea is to keep the car from eating batteries. The car is safe, locked up in an underground garage. I am trying to protect the battery from the alarm system, which eats a lot of Coulombs over time.

I will try to post a digital photo of the installation. It was done by an automotive electric shop, and worked out very nicely.

Problem is, when I turned the kill switch at the end of the day, the alarm went off.

Obviously, there must be some secondary power supply in the system, maybe a sequestered battery or just a big electrolytic capacitor. The blooping and bleeping lasted for about 20-30 seconds.

According to my manual, you can shut off the alarm by pressing the number 1 segment of the key.

This had no effect, but then it never has. How DO you shut off the alarm, in real life?
On past occasions I have gotten it to turn off by inserting the key in the ignition and starting the motor.

Wll, I left the car, battery disconnected, reasoning that the alarm must have been triggered by the sudden interruption of current. This will not happen again until I get in there and turn the switch.

What is the phantom source of power for the alarm? And how do I:

1) keep the stupid alarm from going off in the first place and
2) turn it off if I can't.

Thank you for your insights,


Last edited by mcg; 04-05-2005 at 05:53 PM.
Reply With Quote
Old 04-05-2005, 05:50 PM
mcg mcg is offline
Registered User
Location: Connecticut
Join Date: Mar 2005
Posts: 15
Mein Auto: 530i
unlock doors first?

When the mechanic who installed the disconnect switch demonstrated it to me, he was able to switch the battery off and on without activating the alarm.

Sunny day here, the car was parked outside with the windows open, and the driver's door, at least, was unlocked. The key was in the igntion.

Reading over some other posts here re alarms, I wonder if the trick might be to leave the doors unlocked? Then disconnect? Then lock up manually?

Thank you for your insights.

Reply With Quote

See More Related BMW Stories

Forum Navigation
Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 5 Series > 5 Series DIY
Today's Posts Search
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Re-Activate Alarm shizat63 3 Series & 4 Series 5 12-17-2004 06:18 AM
E46 alarm chirp/beep question kaidoy 3 Series & 4 Series 17 10-11-2003 11:38 AM
Simple Factory Alarm Question.. CWolfey 3 Series & 4 Series 1 08-27-2003 07:52 AM
Group Buy on Euro E46 Cic Alarm highbeam Classifieds 17 08-21-2003 04:17 PM
Alarm question Fingaz 3 Series & 4 Series 14 12-17-2002 06:45 AM

All times are GMT -7. The time now is 05:33 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
© 2001-2015 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms