brake lights on when lights on

[strummer]

hi
  driving today with lights on,warning came on dash to check brake lights,checked and both brake lights are lit up when lights are on,turn lights off and they go off,press brake pedal with lights off they light up as normal,press pedal with lights on(brake lights on also)and brake lights get brighter,anyone got any ideas?

[X5Sport]

Are you sure you are not looking at the sidelights?  The bulbs are dual filament 5W/21W, one covers rear lights and the other the brake lights.  That behaviour matches what you are seeing.  The error could be a bad connection indicating the bulb holders need looking at as corrosion is a known problem.

If you really stand on the pedal you will get another pair of brighter bulbs on as well.  It's called Brake Force Display designed to indicate to the dozy gits behind that you really are stopping and in a hurry!

Richard

[Horizon]

This can be caused by a bad earth connection on the rear light cluster. Run a better earth connection to the rear lights and check if your problem goes away

[strummer]

had a look today,it appears when lights are on the brake lights come on with the rear side lights,when the brak e pedal is pressed the brake lights light up brighter even tho they are single filament,must be more voltage supplied to them when pedal pressed,offside brake light was flickering and found a bit of the plating missing on the light assembly where the bulb contacts,put a bit of tin foil between the contacts and all seems fine,thanks for the replies 

[X5-D-Sport]

As Strummer says, the lower pair of lamps will illuminate brighter with the brakes are applied.

THIS IS NORMAL.

Use identical single filament bulbs on the tail lights, brake lights, reversing lights & fog lamps... all take the same 21watt bulb !

Hope this helps.

[chrisn7]

There seems to be conflicting info in these posts on dual filament or not. Maybe this will help?

http://www.bmwmotorsports.org/pdf/e53/B ... Repair.pdf

[rhinoman]

I think the later e53's had a single filament 21w bulb that just gets brighter when the brakes are used and brighter still engaging the second bulb when pressed very hard. Ours is like that and is a 2006.

[X5Sport]

Looks like that's it.  Realoem shows it as 4 21W long life bulbs so the LCM must run them on a 12V pulsed feed to run them as dimmer sidelights and go to direct 12V un-pulsed feed with the brakes on, plus extra lamps for emergency braking?

Richard

[rhinoman]

[quote="chrisn7"]
There seems to be conflicting info in these posts on dual filament or not. Maybe this will help?

http://www.bmwmotorsports.org/pdf/e53/B ... Repair.pdf
[/quote]

I did this repair to mine this year and its been fine since, couple of hours to do both lights, much cheaper than buying new units.

[Greig]

[quote="chrisn7"]
There seems to be conflicting info in these posts on dual filament or not. Maybe this will help?

http://www.bmwmotorsports.org/pdf/e53/B ... Repair.pdf
[/quote]

I think you!

Just done this to both sides of my rears. The Bulb Holders still seem a little ''shaky' in the holes. But , for now, it seems to have fixed the problem.