fader backlight stays on

[mlytle]

88 M3 with fader in dash above stock cassette stereo...car is low mile, all original.

the backlight for the fader stays on all the time. car on or car off. rest of dash lights work off the main headlight switch, but the fader light just stays on, and on, and on....draining the battery.

i have not gone through all the fuses pulling them to see where it is getting power from yet, nor pulled the fader out yet.

anyone seen this issue before?

thanks.

[earthwormjim]

Do your window switches stay illuminated too? If so, then your door switch might have failed.

I can't remember what situations the fader would illuminate, I deleted mine when I put a Continental head unit in. I thought it lit up whenever the window switches were lit up.

edit:

Just checked the ETM, looks like it should only be lit up when the headlight switch is in parking lights or headlights on.



Use this diagram to trace the wiring, see where your fader switch is drawing illumination power from.

[mlytle]

thanks Jim. nice of you to take the time to attach the ETM page!

nothing else above C302 is on. maybe the "always on radio memory power" source is bleeding though headunit via S345 to the fader light. going to go find the fuse for that and pull it to see. (I have an ETM)

i would replace the headunit with aftermarket, but trying to keep the car perfectly original.

[mlytle]

well, pulling fuse 21 kills the fader light. somthin' ain't right!

[earthwormjim]

Perhaps the feed going to your fader and radio illumination was damaged, and "fixed" by the previous owner by wiring it to the glovebox flashlight charger, or something else that is always hot.

[mlytle]

pulled radio and fader. looked like it had never been out of the car. thinking the fader may be getting back feed from dead SI batteries on same fuse.

[mlytle]

closing this out....the factory, yes, the factory, wired the car wrong. the fader light was connected to the constant power wire for the radio memory.