my cousin just picked up a 06 Z4 about 2 weeks ago, and I tried to replace the license plate light with leds, however i notice after i shut off the cars and all the lights for some reason the leds of license plate is still on, although its dimmer but it's still on. I never have these problem before with all my previous cars but they were all japanese cars..such weird situation..anyone please advise thanks.

(I know this has nothing to do with Acura but we asked the same question on bimmerfest and no one can seem to come up with solution, thought people here may be smarter at this)

 

that is weird

you should test to see if the stock bulb does it. at least that way it could give you an idea if its the led itself, fuse, or wiring. Just throwing some possibilities out there.

 

i ended up putting back the stock ones because i didn't want to drain out the battery, stock ones works perfectly, on when you turn it on and off when you turn off.

For the LEDs, I tried all the bulbs including the strip that i have and every one of them turn dim when i shut off....so so weird~~~

 

This is normal behavior. Some cars are designed this way. My friend's 1999 civic and 07 350z do the same thing. It won't drain your battery don't worry

 

That's not to say that's how they designed it to be, but it's just how the circuitry works. When it's off it has a very low voltage which won't turn on an incandescent bulb but the led will keep running.

 

OP needs a voltmeter.