Radio 12+ Constant Wire no power ?

[BruchaBmw]

As the title implies the "Yellow" 12+ Constant wire for the radio is coming up dead i have checked the fuse under the Hood for the radio and it was not blown, replaced it just in case. The Red And Orange wires are still being powered. Am i missing a fuse somewhere that would cause the wire to be dead.

[revtor]

BruchaBmw: Yellow? Which pin of the BMW radio connector are you looking at? The permanent 12 V is applied at pin 9 and is a red/green wire.

8eights: That's the amplifier wiring - not the radio.

[8eights]

Oopz, got it mixed up, The radio plug locked into place as I recall, been a while.

[BruchaBmw]

Yes its a Red And Green wire going into the stock 17pin connector, and i should have been clearer that it is attached to a Adapter for an aftermarket HU. Which makes it a 12+ Yellow Constant wiring going to the HU. The Red and Orange leads coming from the adapter are receiving power and the ground is properly grounded. I had no issue with the Hu the day before this post and woke up to the HU not turning on. as stated i checked the Fuse in the Front fuse box and it was fine i replaced it anyways.

(Edit) if i use the Orange or Illumination light as the 12+ constant then the device gets power so the only wire no longer receiving power is the 12+ Constant.

[BruchaBmw]

For the time being i have connected the Radio to the 12V Illumination lead which means my dash lights have to stay on to have the radio play.

[revtor]

The illumination wire comes from the dimmer and is a pulse-width modulated signal - not exactly the best choice to feed the radio with and it'll put unnecessary burden on the dimmer.

There's nothing between fuse F36 and the head unit but wiring. You wrote you checked and replaced the fuse but did you actually check there's voltage on the fuse? If that's okay I would start with removing the adapter and measuring voltage between pins 9 (red-green) and 15 (brown) of the BMW radio connector.

[Cup1d]

Same problem here. No power to the yellow 12V constant on. No fuses blown. Is there a fusible link somewhere on this cable? Anybody know?

[Timm]

The 'Hot at all times' conductor is RED/GREEN from Fuse 36