2001 X5 Won't start off own Battery - Help!!!

[wwpxd16]

So I have have a 2001 3L D X5 Sport auto, if it makes any difference. 130,000 miles. I'm having a nightmare with it for the last 6 months and need some help before I commit it to the dealer. Here's what's happening

The car simply refuses to start off its own battery, every morning. Once its jump-started (usually very easily) give it a few mins and its fine for the day, unless you leave a door open or interior light on etc the. It dies within 5 mins.

We are currently having to charge the battery every night, to ensure its good. At first it would go a few days but now its every night without fail. I've been advised that it has some kind of safe mode which kicks in if under a certain volts and that something may be staying on overnight etc. the only thing I can think of is the stereo/sat nav/hand free kit as that's been blocking itself quite a bit (the radio intermittently stops until either the sat Nav talks or the phone is removed from the range).

Anybody have any checks a simpleton can do ? I'm reluctant to put it into the dealer to be told its big bucks.

Yes I've replaced the battery, they also checked it was re-charging and said it was

[percodan]

Something is obviously faulty and causing a current draw.. I see you're in the UK, I believe you guys had Trimble traffic monitors that were notorious for doing exactly that. Phone modules can also go bad and draw current, and less commonly the nav units. Another common suspect is the final stage resistor for the climate control blower, they can actually cause the interior fan to run when the car is off and flatten the battery.

[wwpxd16]

Thanks for the pointers, how can I check them to start with ? I assume I'd notice the fan staying on when the car is off

[JCL]

Just about any module can stay on in error, and cause the vehicle to not go into sleep mode, as it is designed to.

Do a search on threads relating to checking parasitic current draw, and sleep mode. What you need to do is measure the current at the battery with a mA meter, and watch to see how it drops over time (20 minutes). If it doesn't drop, you then pull fuses one at a time until you determine what is causing the current draw. This is complicated a little by having to do this with access to the multiple fuse box locations and the battery, since opening a door can cause a current draw. You also can't disconnect the battery to install the mA meter, since that resets it. You need a small jumper cable, in parallel with the ammeter, which you then remove, and also an understanding of electrical connections.

The total parasitic draw will be higher than the small draw you get from any single module; it is just that the small draw they have prevents the vehicle from going into sleep, ie the effect is greater than simply the current drawn by something like a telephone module, or whatever. It also doesn't have to be a module you are using or are even aware of, just one that BMW installed originally.

Good luck. I'll look for a link for you.

Edit: Try this one: http://www.xoutpost.com/bmw-sav-foru...dies-fast.html

See the link in post 42.

[wwpxd16]

Chaps, thanks for the assistance to date. I have now had an electrical/audio centre check it all through with diagnostics etc and they have concluded the following:

The car goes Into sleep mode without problem and draws very little when in this, they said something like 20ma which is better than most hatchbacks ?

The audio, cd, sat Nav, TV etc is not drawing anything or leaving it alive during sleep mode

They had the car overnight and it was dead the morning they tried starting it.

The battery they felt was possibly a little under-powered or dead (although it was the max spec when fitted 6 mths ago), so it was swapped for new under warranty. Having discussed it with the battery centre they confirmed the battery was rated for the car. So back to checking other culprits.

They checked the Starter motor which was drawing around 400ma on starting, this concerned them as apparently it should draw less than half that ??? So maybe this is killing the battery. My concern with that is why only overnight does it die and not during the day when trying to crank ?

So still no closer to finding out the problem, the plan now is to test it again cold in the morning to see what the starter is pulling from cold, maybe if its even more again this is the fault. My guess is it will start fine tomorrow as its a brand new battery.

So any thoughts ? What next ? Would a BMW specialist be able to check anything better/mechanical or should I try a new starter motor first ? Anybody have issues with the starters ?

Thanks and sorry for long post

[Bargain Bucket]

The 3.0d is has a known starter motor issue. Once they have aged a little, the starter can draw a massive amount of current (i.e. 400A - not mA), especially in cold weather as we have right now. You probably won't experience this problem once the weather warms up. IF this really is the issue then the answer is to replace the Magnetti Marelli starter motor.

[TerminatorX5]

if nothing is drawing the power from a "good" battery overnight, why is the "good" battery dead in the morning? strange...

400 Amps is a little too much, as a matter of that much of amperage can start a fire... there could be a mechanical issue with the starter, when something binds and required more power to overcome the binding, and once "unbound" is fine for a day... you might be on the right diagnostic path with the starter...

[wwpxd16]

Were back where we started!

Went to collect the car today and guess what...it wouldn't start. They checked the battery before the left yesterday it was fully charged ready to go, this morning it was dead, that was even before they had attempted to crank it over! So its not the starter (although clearly that's pulling more than it should too).

So now the garage has suggested they to back to the beginning, this time the want the car for 3 days, or in fact nights to monitor it. Something must be o ing on and drawing enough power to kill the battery overnight ???? They have suggested setting up a camera to record it and hopefully that will find out what's going on. Obviously its going to cost me so is it worth it ?

If I started pulling fuses out overnight and trying to start it in the morning with say the sat Nav, phone, air con etc all disabled would that work ? Or do would I have to physically remove each module to eliminate them ?

Its really starting to get on my nerves now

[TerminatorX5]

pulling fuses should work - as long as you are pulling the right fuses...

for a battery to discharge overnight, you need to have a consistent draw on the battery for the extended period of time, or a quick short - the quick short will leave burnt marks...

all of this assuming that the battery is a good battery, and you say that you have replaced the battery couple of times... but, if the battery is not good, it may discharge itself from internal malfunction, when the chemicals leak into each other's chamber - the so-called dead cells, or even shorted out cells...

setting up a camera - are they expecting a little gremlin actually do some physical harm to the car??

do the ultimate test, at night (or, whenever you are finished with the car for the day) disconnect the negative terminal of the battery completely from the car (i hope you have a garage) and in the morning, when the car would have been dead otherwise, try reconnecting the thing and then try starting the car... if you have a multimeter, measure the battery at night, and then measure it in the morning, before attaching the terminal...

this test will eliminate the battery from the picture, and then you can concentrate on the car...

[wwpxd16]

I'm pretty satisfied the battery is good, since its been replaced for a new on and failed to start after its first night, plus we've swapped the battery before without success.

I'm not sure what the camera option will do tbh. I think they are hoping the will see if he sat nav is coming on etc, I'm not convinced but what choice do I have. My understanding is they have got the readings from the battery to say its good. If I do disconnect the battery overnight, will it remain alarmed, or is there a chance that the immobiliser could go off, or worse still need resetting etc ?

Its going in after Easter so I will start pulling fuses, do you think if I pulled out everyone that's not important (leaving things like alarm etc) to see if the fault goes away then re-introduce each until the fault returns is the best way to go ?

Another option I thought about was fitting a battery isolator ? Would this work, or would it shut down the alarms/codes etc when not active overnight