Interior Map Light Issue

[ZeroDfx]

The interior lights will not go on in my wife's 2003 G35 Coupe when you open/close the doors, turn the car off, or when you hit the switches to turn them on manually. Anyone know if/where there might be a fuse for this?If so, where the heck is the fuse box?I found the small one in front of the battery, but is there another one somewhere? I've done a SEARCH here with no results, and the manual makes it look like there is a second box.Anyone? I'd appreciate the help.TIA, Nick

[SneaKe]

could be wrong, but its under the dash, driver's side above the left foot rest.

[pippen99]

Same thing happened to my 03 coupe. You can spend an hour shoehorned into the footwell pulling fuses one by one or try this. Pull the positive battery cable, wait five minutes and reconnect. This will reset the BCU and cure your problem. It cured mine. If that doesn't work then screw yourself into a pretzel and have at the fuse block. Good Luck. (P.S. this will also kill your radio presets)

[ZeroDfx]

That certainly sounds like the easiest approach to start from; if that doesn't work then I'll figure how to get myself twisted and contorted enough to find the fuse box. I don't care about losing the radio presets as we use the CD player predominantly.

How did you come upon this solution? Were you assuming the car's operating system was made by Microsoft and it needed rebooting?

Thanks, Nick

[pippen99]

I found it in some forum (not this one). This was almost 2 years ago so I can't remember where. The BCU controls all kinds of things like the interior lights and such. If the problem returns then the unit is faulty and will have to be replaced (lots of dollars). GOOD LUCK!

[Sentientbydesign]

What the heck is a BCU

If you go to autozone or an electronics store, you can buy a little tester that allows you to test the fuse without pulling it.

The top of the fuses have those openings in the plastic for a reason

[Beancooker]

BCU= Body Control Unit... also known as a BCM= Body Control Module.

It's like an ECU that controls the less mechanical parts (engine/fuel injection/etc...), like the lighting system, guages etc...

[ZeroDfx]

Same thing happened to my 03 coupe. You can spend an hour shoehorned into the footwell pulling fuses one by one or try this. Pull the positive battery cable, wait five minutes and reconnect. This will reset the BCU and cure your problem. It cured mine. If that doesn't work then screw yourself into a pretzel and have at the fuse block. Good Luck. (P.S. this will also kill your radio presets)

Well I'll be darned, but that worked!! Thanks a bunch.

I pulled the battery cables and took the opportunity to rough up the terminals and posts with a wire battery cleaner brush, and by the time I reattached them, the interior lights came on when I opened the doors! I can't imagine what may have caused them to go off in the first place, but they're back on.

Nick