ianbmwe60

hi all I love this site and people are great to respond thank u all any way is their a way to check if the ibs is ok

BimmerFan52

Why do you think it is bad?

The most common failure for IBS is that it repeatedly wakes up the main computer ( which will quickly run down the battery), even though there is no unusual load. This was a common failure of the IBS in the first couple of years of the E60 series but it is less common in later models.

To test if the IBS is running down your battery, disconnect the blue connector on the two conductor wire coming off the negative battery cable (pictures are available on this site if you search).

In rare occasions the IBS can interrupt starting and disconnecting the IBS will confirm failure if the car suddenly starts.

Leaving the IBS disconnected for extended periods will not hurt anything.

ianbmwe60

hi tanxs for your reply I disconnected the ibs sencor and had it off for over a week and no difference weather ibs is connected or not and the orange light by gear stick goes out after 20 min.my battery just goes down even if I charge it full.now I only drive 10 15 min every day and go no were wk ends when battery is weak it sets off red air bag light

BimmerFan52

You were correct in looking at the orange light near the gear shift to determine if the car is going asleep. If the light is staying out during the whole time the engine is off then you have probably narrowed your problem down to three possibilities;

1. There is some other parasitic drain on the battery when the car is off that is not waking up the ECM, but is draining the battery.

2. The alternator is failing, and the car is being operated, even at your short driving distances, almost entirely on the battery which will run it down quickly.

3. The battery is at the end of its life.

To test possibility #1, fully charge your battery using the terminals under the hood (ideally on Friday if it can sit the whole weekend). Then carefully disconnect and insulate the negative battery cable end so it can't fall back and touch the battery terminal. On Monday reconnect the battery and start the car. If you do this twice with no loss of battery power you can be begin to search for what is drawing power from the car at rest.

To test possibility #2, start the car and wait 15-20 seconds for the alternator to spin up and start producing current and then measure the voltage across the two battery terminals with a multimeter. A multimeter is about $5-$8, and easy fairly easy to use (youtube has tutorials on how to set up to measure voltage). The system voltage should measure approximately 14.3V - 15.0V. This test is not an absolute positive as a failing voltage regulator on the alternator can be very intermittent, but it is a start. You can also repeat this measurement at various time during your trips before you turn the car off. There is also a voltmeter that will plug into a 12V socket in your car that you can buy (about $12) that allows you to measure the system voltage anytime at a glance during your drive.

If both test #1 and #2 indicate that you have no parasitic drain and the alternator is charging the battery then replacing the battery is in order. You can double check your theory by having an auto store check the battery with a hand held computer (if auto stores provide the same free testing services in Ireland that they do in the US).

Finally, a tip if you install a new battery. Short trips are very hard on any battery, as the energy removed to start the car takes quite a bit of driving for the alternator to put that power back in. Any time the battery sits with less than a full charge a chemical reaction in the battery deposits sulfur crystals on the battery plates. If the battery is then fully charged within a short time these crystals dissolve back into the acid solution. But if the battery is constantly short on charge these crystals sit for a long period and eventually harden, blocking the ability of the battery plates to absorb future charges. The battery becomes weaker and weaker and until the crystals finally block the battery from accepting any meaningful charge at all.

In older engines with carburetors engines required a long cranking period before the engine would start. An early warning of a weak battery was an audible slowing of cranking. However, new engines start so easily that there is no warning as the battery approaches its starting threshold, until one day it just doesn't crank at all.

I suggest you purchase a computer chip driven battery tender which you can use weekly to keep your battery "topped up" and in a state where sulfation of charging plates is minimized or eliminated, greatly extending battery life.

ianbmwe60

thank u so much for all that info that was very helpful to me im going to try it now and let u no tanxs again

ianbmwe60

I checked the voltage after a few min of car on but I never drove car 2 day and it read 13.80 at idling

BimmerFan52

Sounds low,especially if IBS is still disconnected. With IBS disconnected the CAS defaults target system voltage to about 14.3V.

ianbmwe60

I noticed under the passenger seat at the matt sencor the cable that goes from it to the seat belt it was hanging down in a lope shape and touching floor but all looks intact wud that set off airbag light should that be neathly hidden

BimmerFan52

I doubt it.

If you make a positive cause and effect between a low battery and the airbag light then troubleshoot the battery.

However, you may have two problems simultaneously, and correcting the battery may not correct the airbag light.

Are you aware of passenger seat occupancy mat recall (and know that it was addressed on your car)?

ianbmwe60

I read about this yes and also read about bypassing it do u no how this works how do these set the lights off