I've started replacing my interior lights with LEDs - I've changed the main dome light to orange and the foot well lights to orange to match the dash. I figurured while i was at it, I may as well change the others, so I changed the glovebox light and the rear boot light to festoon LEDs as well.
This is where I've run into a problem.

The rear boot light won't turn off.
After all the doors are closed, it dims as usual, then stays glowing, and occasionally flickering bright enough to distract me while driving (with the rear seats down).
I put a voltmeter across the terminals, and found without a bulb, it reads:
12V : Doors open
10.5V : Doors closed
11.5V : Doors closed engine running.

When I put the incandescent bulb back in, and put the voltmeter on, it reads 0V with the doors closed.
With the LED bulb in, it reads 2V lower than the voltages above.
I guess the resistance of the LEDS is much greater than the incandescent.

It strikes me as very odd that there's such a high voltage when I would expect zero. The main dome light goes to zero, and the glovebox light is mechanically isolated, so it's not a problem.

Does anyone have an explaination, or would be able to measure the voltage across their boot light terminals (bulb removed) with the doors shut?
I wonder if I've got a wiring fault.

Just done some more investigating....
It only flickers (like a strobe in my boot!) when the park/headlights are switched on.

This is going to drive me crazy! :confused:

did some more checking with a voltmeter, and it's definately not a wiring short.

The positive wire on the boot light never drops to zero volts.
With the ignition off and all the doors closed, it stays around 10V and a few 10ths of a milliamp of current trickle through.
With a LED bulb, because of the lower resistance, it will glow.

Stupid MINI engineers. wasting valuble power! :mad:

If my battery goes flat when I park my car for 10 years, I'll know what to blame. :rolleyes:

You got me curious, so I took my scope out to my 2002 MINI Cooper 5-speed and I hooked it up to the hatch-light with the bulb removed.

I saw the positive signal go to zero whenever I closed the door.
I tried key-off key-on, headlights off, headlights on, and park-signal-on.

I did see that the signal never goes to 100% on though.
http://www.mini2.com/galleries/data/500/HatchLight_1.jpg

But it's only about 50 microseconds out of 4 milliseconds, so it is 98.75% on. :)
http://www.mini2.com/galleries/data/500/HatchLight_2.jpg

I'm not sure what's going on with your MINI. Maybe you should add a 1K resistor in parallel with your LED.

i hit this problem too - no idea why as i'd like a red light in the boot!! but when my car didn't get driven for a while this DRAINS the battery!!

and had to get a couple of jump restart as the mini had died - so its now been taken out and the old bulb put back in!