Hey guys I need some trobule shooting help. I drive a 1993 E32 740I. Over the past few months I have been losing some lighting. First interior lights then dash then radio. Fuses are ok. Now I keep blowing a fuse for right rear runing light. I replace fuse and it blows immediately. Any ideas? Could It be the battery? Occassionally ill drive a while in the day and my radio lights will come back. Thanks for your help.

Checked battery, its fine. Any ideas?

I would bet the rear light has a short to ground causing excessive current flow because of lower resistance. But the rest I am not sure but is probably caused by an open.

I would bet the rear light has a short to ground causing excessive current flow because of lower resistance. But the rest I am not sure but is probably caused by an open.

Ill check the ground. Excuse my ignorance but what does "caused by an open" mean?

Its the "mustard" relay!! look in your fuse box in the engine bay. there will be a mustard color relay box in the middle of the fuse box. pull that relay out and take the shell off of it. inside there is a little board with stuff soldered on it. sometimes the solder on the board cracks and makes a bad connection. look real carefully at the solder and see if the solder is cracked. if so, just remelt the solder back on the board. Im pretty sure that this will fix it. Im like 99 percent sure that this is your problem.

- Steven

Its the "mustard" relay!! look in your fuse box in the engine bay. there will be a mustard color relay box in the middle of the fuse box. pull that relay out and take the shell off of it. inside there is a little board with stuff soldered on it. sometimes the solder on the board cracks and makes a bad connection. look real carefully at the solder and see if the solder is cracked. if so, just remelt the solder back on the board. Im pretty sure that this will fix it. Im like 99 percent sure that this is your problem.

- Steven

Ill check it thanks.

Ill check the ground. Excuse my ignorance but what does "caused by an open" mean?

A open circuit is a circuit that does not have current flow because it is not complete/closed. An open just saying that there is not current flow and is usually caused by missing a power or ground/something else that I can't remember or basically anything you can test with a test light.

For example, my car is missing a ground for the rear passenger side tail light so it is back feeding through the system causing a lot of warning lights to go off until the electricity finds a ground.

have a very good eye to look at the cracks in the board.

always use a volt meter. "try" not to use a light detector. a volt meter will always tell you how many volts you have so you can see if you have a "voltage drop". a light detector will turn on the light with 1 volt, when you need 12 volts. giving you the wrong trouble shooting information.

good luck.
-Steven

have a very good eye to look at the cracks in the board.

always use a volt meter. "try" not to use a light detector. a volt meter will always tell you how many volts you have so you can see if you have a "voltage drop". a light detector will turn on the light with 1 volt, when you need 12 volts. giving you the wrong trouble shooting information.

good luck.
-Steven
Thanks, Steven the mustard relay was the problem with the runing lights. FIXED.
Any idea on what the problem with the interior lights is?

Didnt work. Any other ideas? Please help.:)

Remove the interior light in the front and open the switches inside (there are 3), sometimes these switches get damaged. Maybe by that you get a short circuit. Also check the wires, also the wire loom which goes into the doors for the door lights if you have that. Wire looms from A-pillar into the door often break.
Here a sample
http://www.pagaduan.org/bmwe32/images/tuer_h_l_0.JPG
http://www.pagaduan.org/bmwe32/images/tuer_h_l_1.JPG
http://www.pagaduan.org/bmwe32/images/tuer_h_l_2.JPG
http://www.pagaduan.org/bmwe32/images/tuer_h_l_3.JPG
and here a broken light switch
http://www.bimmerboard.com/forums/posts/223270/
and that are for example the innards of a headlight switch
http://www.bimmerboard.com/forums/posts/169009/