Autolights E53 - battery drain???????

[Trikeman]

Hi All,
first technical question. :-[

Symptoms - parked up X5 last Saturday (so just over a week as done many times) noticed this morning no flashing light by mirror (alarm indicator). Anyway, this evening went to check out - nowt, no remote lock opening, no dash lights - in fact nothing at all.

Crawled through car to get tailgate open, removed everything, got to the battery and it was as flat as the proverbial witches......

Only thing I did different last weekend was use the automatic lights, something I have never used before. Now I 'thought' if I knock the ignition off and lock up on the remote as normal the auto lights would go out - which they did. Have heard, and not sure if this is true though, but if they are left on, as in switched to Auto, the system can cause a quite high drain even though the lamps are actually off.

Anyone know if this is true? Never had any issues with the 'ole tank' before like this. I understand it could be the battery just died, just trying to think of anything that may have caused this sudden 'death'.

Anyway, trying to re-charge the battery tonight and see what happens tomorrow, but would be interested if anyone has experience of this issue with the auto lights.

Regards and Thanks,

Trikeman. 

[X5Sport]

My E53 was left with Auto lights selected all the time.  Never had a battery drain issue from that.  Same on my current X6.

Normally colder weather, or short journeys can highlight an underlying issue, but it hasn't exactly been cold (yet!).

Worth checking the voltage under the bonnet - which is where you charge it from too using the jumper points (and as stated in the manual).  Not necessary to dig into the car to get the battery out.

If the battery is more than 5-6 years old then it may just have died without warning.  It should have a 4-digit code for the production week/year on it.  If it has gone flat during that time then it's service life will have shortened.  Once you are up and running, it will be worth checking the voltage with the engine running too.  It should be around 14.4V DC

[Trikeman]

Thanks X5Sport for getting back. 

These are 'strange' things for sure,,,,. Charged battery overnight and checked and refitted this afternoon, no probs there. Keys in ignition and fired up OK - dash covered in lights, Read here that to turn steering from one lock to the other and should cure dash lights. Tried that and viola,,,,, all dash lights go out and all back to normal. I took it for a spin and no probs there - checked charge rate and around 14.2-4. Locked up and 16 mins later it 'went to sleep'. 

Not too sure what caused the hiccup, checked for draw on fitting the battery and no more than expected (tailgate interior lamps draw). Ordered new battery just in case though.

Again, thanks for the contact.

Regards,

Trikeman. 

[X5Sport]

Check the battery volts 4 hours after last use, and once the car is asleep again.  Should be around 12.4-12.6V at the charge points.

If lower then battery is suspect.  After that you will need to borrow a current clamp and check the current draw is <90mA, preferably well below.  If it's much above then you have a parasitic draw which is a pain to track down. >:(