[aggieEVO]

Hey All,

Bought my 09 335i sedan a couple months ago. As the weather has gotten colder, the radio has started having issues. It started out with the head unit turning off for a quick second. Now there are times it won't come on at all. Most often it's in the morning when the car is cold. If it warms up to above 60 during the day, it works around 90%. I've had the SOS error pop up. Most threads I've seen have pointed to the sat module. My car is sat ready but doesn't have a module installed.

Could it just be the head unit?

09 335i Msport. Logic7 sound.

Thanks in advance.

Brady

[ctuna]

Could be your battery is low and IBS system is turning stuff
off.(like the stereo)
Battery problems are aggravated by cold.
I would try putting a long slow charge on your battery to
see if it solves some of the problem's before doing anything
else.

Read the first electrical pdf about IBS

electical e90 pdf
http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

Also if I would check your amp to see its not wet.
Amp's going out due to leaks are a common problem in these.
Symtoms are Head Unit appear to function but sound is gone
or Staticy at first before it dies altogether.

Water Drains
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showthread.php?t=1566005

[aggieEVO]

Thanks for the info. I'll check on the battery and amp for sure.

I never get static, it just goes off and on suddenly. Screen goes blank but buttons are still illuminated.

Originally Posted by ctuna

Could be your battery is low and IBS system is turning stuff
off.(like the stereo)
Battery problems are aggravated by cold.
I would try putting a long slow charge on your battery to
see if it solves some of the problem's before doing anything
else.

Read the first electrical pdf about IBS

electical e90 pdf
http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

Also if I would check your amp to see its not wet.
Amp's going out due to leaks are a common problem in these.
Symtoms are Head Unit appear to function but sound is gone
or Staticy at first before it dies altogether.

Water Drains
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showt...hlight=battery
https://www.e90post.com/forums/showthread.php?t=1566005

[aggieEVO]

Charger is hooked up as we speak. It's been on for about an hour and hasn't switched over to "tend" mode. Maybe I should check the date on the battery.

[ctuna]

Usually takes about 5 to 8 hours for my ctek to top off
my battery .
Average battery life is 6 years
my Interstate is going on 8 plus but I top it once
or twice a month on the ctek 4.3
These cars are known battery hogs.

[aggieEVO]

Just a little update. I left the battery on tend all night Sunday. Monday morning it was about 40 outside. Car started, radio went off and didn't work until afternoon. It's been 60+ the rest of the week and it's worked fine. I haven't had a chance to dig into the amp, but I kinda doubt it's wet. Hopefully I can check it this weekend.

[ctuna]

Had a Pioneer Head unit once that wouldn't work when it was cold
it was under warranty so I got it replaced . I can only speculate
it was a cold solder joint somewhere.