Rear Defroster

[Jean]

What fuse and/or relay controls the rear defroster ? I replaced the bulb in the rear defroster switch with a good bulb, but it does not light up still.

Thanks.

[franco90]

picture please

[Jean]

picture please

Of the switch ?

[franco90]

maybe you got a bad switch

[Jean]

Is there a fuse or a relay though still ?

[franco90]

I dont know sorry I know when my light did not come on I replace the whole switch and it works now

[Jean]

Was told to checked fuses 8 and 23 "Fuses 8 and 23. Counting from the Front Passenger side of the box the first row is fuses 1 - 15. The next row is 16 - 30."

Both are ok. Does anybody know if there is a "defroster" relay somewhere ?

[DaveSmed]

That would be a no. Fuse 8 is the one you need to be concerned with, 23 is for the parking lights. Fuse 8 is a green 30A fuse. Swap it with another green 30A fuse from your fusebox just to completely eliminate the possibility of an open fuse.

Is it just not lighting up or have you verified no power at the back window? FWIW, those switches are a common failure item as BMW did not use a relay, so all of the current passes through the switch contacts, and the rear defroster doesn't have a timer, so absentminded owners are free to leave the thing on for a month whenever they drive around.

[Jean]

That would be a no. Fuse 8 is the one you need to be concerned with, 23 is for the parking lights. Fuse 8 is a green 30A fuse. Swap it with another green 30A fuse from your fusebox just to completely eliminate the possibility of an open fuse.

Is it just not lighting up or have you verified no power at the back window? FWIW, those switches are a common failure item as BMW did not use a relay, so all of the current passes through the switch contacts, and the rear defroster doesn't have a timer, so absentminded owners are free to leave the thing on for a month whenever they drive around.

Thank you, I am going to check the voltage at the rear defroster tomorrow. I just wanted to confirm if there is nothing else I need to look for inline, other than the fuse.

[M42Technik]

Yours actually works? And you're in Cali?

Shit I need that more than you!

[Jean]

Doesn't work, that's why I am trying to see what's wrong with it, checked the #8 fuse with a DMM, it's good. I am going to check if there is any voltage at the switch tomorrow.