[number9]

Hi. About 20 odd seconds after I have locked the car and the interior door lights have dimmed,  the LCD panel which shows the door lock status and milometer comes on. No text, just a blue hue backlight. Any ideas, anyone please? I've disconnected the battery for a few minutes and reconnected but no change.

[Shambles]

Disconnecting the battery would have been my first suggestion.

For how long did you leave it powerless?  The minimum is arguably 30 minutes to allow the BCM to deplete.

[number9]

The bad news is that my battery was totally discharged when I went to drive to work this morning.  The good news is I've charged the battery and it appears the display has reset.. odd.

[tw2005]

Yeah, that's an odd one. have not seen that yet.

[nzenigma]

Yeah, that's an odd one. have not seen that yet.

I have. Way back, so cant remember why or if it self reset.
Obviously something has switched on and has drawn a heap of current- eg flat battery ( assuming it is a good one???).
A faulty door switch? 
If it keeps occurring you need to leave an ammeter from disconnected battery to car earth , then measure across fuses.

[number9]

I suspect the battery maybe getting on a bit and ready for change. You think this may have caused it?

[nzenigma]

I suspect the battery maybe getting on a bit and ready for change. You think this may have caused it?

Cant see why it would. Mind you the converse also applies 

What I do know is that if something was drawing a bit of current, a dodgy battery probably wont last the night. So that is where you start. Change it. At least you are good to go in the morning.

When you switch off, various ECU controlled  functions take their time to close down. I have one car that draws a diminishing current load for about 15 minutes before it is entirely in sleep mode.

[number9]

New battery. Problem solved.

[nzenigma]

New battery. Problem solved.

Thanks for the heads up. Good result. 

[number9]

Thanks. Relieved it was this simple but I was thrown by the light coming on of its own accord.