What have i done wrong...

[MD13 459]

So I tried installing a sub in my e46 today. It came with an alpine h/u and alpine amp in the boot but the sub was absent. Spent all day checking the boot wiring and mounting the amp more securely. Test it and set the gain all good but time consuming so far. Then I start it and something is making a motor noise in the dash - either the h/u or the climate control unit. Keeps going even when the car is off and the key removed. To get it to stop I have to disconnect the battery... I did not touch anything in the dash. All work was done in the boot...

Ideas?

[zero 1160]

So did you install a sub?

Just trying to understand the variables.

[aja540i 1896]

Does the headunit have a cooling fan in it?

[MD13 459]

Not sure - has crossed my mind... Have tried turning the h/u amp off to no affect. Have disconnected the amp turn on lead and rca's to no affect. Sigh.

H/u out next.

[zero 1160]

Sounds like this problem;

http://www.bimmerfest.com/forums/showthread.php?t=523898

Because you are doing audio stuff you are more likely to hear these other noises as u are listening more intently.

[MD13 459]

The climate control unit! Pulled it out, retested and no noise. Plugged it back in but hanging loose and the little fan in the back is noisy. There seems to be some other noise behind the dash cluster also... This only stays for 5 seconds or so then stops. So possibly the resistor you've mention Zero or this:

http://forum.e46fanatics.com/showthread.php?t=298527

Relief thinking I haven't f**ked this up but annoying too!

[zero 1160]

The resister is a common fault, and not too hard to fix.

Good luck.