No Audio from speakers
Thread Starter
Member
Joined: Dec 2012
Posts: 75
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From: Massachusetts, USA
2011 C300 4MATIC SPORT
No Audio from speakers
I have a 2011 C300 4matic sport with the harman kardon audio system. Last week, I randomly lost all sound from my speakers no matter the source (AM, FM, Satellite, Nav, Phone, Etc.). I've been trying to look up a fix for it without having to bring the car to the dealer since I have an aftermarket sub and amp installed in the trunk and don't want them to simply blame it on that and void my extended warranty.
Today, I turned the car on to Accessory without turning the motor on and then pulled Fuse # 26 under the hood with runs the comand system. I checked the fuse, a yellow 20A fuse, and it appeared fine. I plugged it back in and my audio started right up with no issues. So I turned the car off and took the key out, installed the fusebox cover and shut the hood. Went and started the car and the audio was out again. So I pulled the fuse again and it worked again, no problem, until I turn the car off fully.
Why would this be happening and does anyone know a fix?
From what Ive looked up could be the Comand System itself is bad OR could be a bad factory amp. Both are super expensive to replace if not covered by the extended warranty OR if the service tech deemed my warranty void due to the aftermarket sub and amp install in the trunk...
Today, I turned the car on to Accessory without turning the motor on and then pulled Fuse # 26 under the hood with runs the comand system. I checked the fuse, a yellow 20A fuse, and it appeared fine. I plugged it back in and my audio started right up with no issues. So I turned the car off and took the key out, installed the fusebox cover and shut the hood. Went and started the car and the audio was out again. So I pulled the fuse again and it worked again, no problem, until I turn the car off fully.
Why would this be happening and does anyone know a fix?
From what Ive looked up could be the Comand System itself is bad OR could be a bad factory amp. Both are super expensive to replace if not covered by the extended warranty OR if the service tech deemed my warranty void due to the aftermarket sub and amp install in the trunk...
Super Member
Joined: Oct 2014
Posts: 701
Likes: 103
From: Ontario, Canada
2009 C63 AMG, 2010 C250 4Matic Sport
I'm wondering if the aftermarket AMP is having issues playing nicely with the MOST network in the car. I swapped the deck in mine with another OEM 6 disc changer and initially I couldn't get sound because I had a fault code stored in the head unit control unit. something along the lines of "MOST Network ring broken".
My basic understanding of that is the whole media system of the car can stop working correctly if communication between media devices (head unit to amp, etc) is broken which can store a fault code like that. Perhaps the aftermarket amp is causing some errors there.
If you have any way to get the car scanned for fault codes with a STAR diagnostic system, that might be a place to look for problems.
My basic understanding of that is the whole media system of the car can stop working correctly if communication between media devices (head unit to amp, etc) is broken which can store a fault code like that. Perhaps the aftermarket amp is causing some errors there.
If you have any way to get the car scanned for fault codes with a STAR diagnostic system, that might be a place to look for problems.
