or_550i

TL;DR When you put the key in the ignition and press the start button - nothing happens - the car won't start. The only lights on the dash are the SRS and brake light. This is a failed IBS sensor (it shorts the BSD [bit serial data bus]).

I was away on a trip when a neighbor called to tell me that the car alarm has been going off for short periods all day long. Normally, car alarms start going off when there is a low battery level (a last cry for help before dying). I thought I had prevented this sort of thing from happening by attaching a "Battery Tender JR" to the chassis and the positive side of the battery (so that IBS was in the loop).

The alarm shouldn't be going off. The car is parked in my driveway, in suburbia, under a cover. I know it's not getting broken into.

I called up my buddy who went over and tried to jump start the car and take it for a spin only to discover that the car wouldn't start; even with a jump.

Symptom of a faulty IBS (Intelligent Battery Sensor):
Put the key in the ignition and the radio, srs light, and brake light on the dash work but the car won't attempt to crank over.
Key in ignition, foot off brake pedal, cannot start get to acc mode (pressing start button twice); pressing the start button twice just turns off the ignition.

There is an SIB from August 2006 about it:
SI B 61 07 06

Once removing the IBS BSD wire (two wires in a three contact connector) the car will crank fine. How annoying.

AchtungE60

Mine has been gone long ago......... ridiculous,

or_550i

Did you replace it or just disconnect it? The [new style] replacement is $259.19 in parts and then coding! Argh. This better be a good will fix since the SIB would be under the year of my e60.

selbycy

Can someone take a picture of the actual IBS connector?
I "think" I removed mine, because all my error messages disappeared for a week or so, but now they have started to come back

or_550i

It's a small connector. I'll take a picture of mine when I take the trunk apart again. It _shouldn't_ cause any errors - it simply prevents the car from starting.

DavidF

I am going to guess that the IBS is fine and that the battery has a dead short and needs to be replaced. You can do all the charging and jump starting you want, but a shorted battery will keep the car from starting. YMMV.

or_550i

I am going to guess that you did not read the SIB... Drove the car 200miles today... Battery is fine.

AchtungE60

i replied to your other post.

I took mine out. I'd never replace it with a part that will be the same.

or_550i

I'm on the fence on replacement or by-pass. Apparently there have been two major changes to the IBS design since my production date (late 2005). It'll be $260 in parts not including the "re-coding."
Although, I'm curious as to why a BSD device would need re-coding; it's supposed to be a mostly dumb device that reports and does not interact.

The only long term problems I see with removing IBS are: battery over charging and a dead battery over a long period of rest (since IBS would be unable to monitor the battery and decide *not* to turn off the accessory electronics).

AchtungE60

Mine has been out for years, no problem....also I am not using OEM battery. I am using an Everstart Maxx 94R for $75 that has more CCA. I'll replace every 3 yrs just because I can on warranty. Doesn't shut off electronics etc...many people have taken them out. In fact I got the car from the original owner which was a BMW tech at the dealership who happened to be my friend. I was reading about taking it out and decided to do so. When i couldn't find it I called him to ask him what I was looking for. He said he beat me to it.