[msportmk4]

Hello, I'm new here so sorry if there is any issues with where i posted this.

I recently installed a amp/sub combo in my 2010 328i w/ base audio

Technic never responded to my email so instead of going with the harnesses for the sub connection I tapped into the underseat speakers and soldered them on. Used a LOC to convert signal and the rest is stuff most people already know. Everything worked fine for about 3 hours.

I park the car, wake up the next morning and I have no door chimes, SOS malfunction is on the dash and the CIC doesn't turn on. *** My CIC unit before the sub install would turn on the with the car, go to an orange/red screen, turn on and function normally for about 10 minutes, then go into an a 5 minute loop of restarting untill eventually powering on and functioning normally until the car is turned off. ***

So this led me to believe my CIC failed (which is apparently rare? correct me if I was misinformed). After buying a replacement unit from a 335i and installing it, I had a coder try to connect and program the unit and he told me he cannot access the CIC because it is not powered on..

Is it my own stupidity for trying to install aftermarket audio equipment or could it be a MOST issue?

Any ideas?

[ctuna]

The first thing to check when there is no Power Is the Battery.
These cars have an IBS system that will turn stuff off if the
battery has been depleted.

When you work on the car or any time the car is awake it's depleting
the battery. If the sub amp is not wired in away that it allows the car
to go to sleep and the amp never turn's off it will deplete the battery.

electrical pdf
https://www.google.com/url?sa=t&rct=...,d.cGU&cad=rja
http://www.shrani.si/f/G/fL/2lp3YVG1...hicle-elet.pdf
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

[msportmk4]

Originally Posted by ctuna

The first thing to check when there is no Power Is the Battery.
These cars have an IBS system that will turn stuff off if the
battery has been depleted.

When you work on the car or any time the car is awake it's depleting
the battery. If the sub amp is not wired in away that it allows the car
to go to sleep and the amp never turn's off it will deplete the battery.

electrical pdf
https://www.google.com/url?sa=t&rct=...GU&cad=rja
http://www.shrani.si/f/G/fL/2lp3YVG1...hicle-elet.pdf
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

Originally Posted by ctuna

The first thing to check when there is no Power Is the Battery.
These cars have an IBS system that will turn stuff off if the
battery has been depleted.

When you work on the car or any time the car is awake it's depleting
the battery. If the sub amp is not wired in away that it allows the car
to go to sleep and the amp never turn's off it will deplete the battery

How do i check a battery other than voltage?

[ctuna]

voltage is the most obvious measurement.
Above 12.6 is good 12.4 is marginal.
Fully charge battery and measure drop overnight to
see how much charge (voltage is lost)