2014 E350 Audio Issues
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E350
2014 E350 Audio Issues
Hello there, I have a 2014 E350 that has the dreaded audio issue, I have replaced the Sirius receiver in the trunk and just replaced the amp and still do not have power going to the amp. Checked all fuses, went in engineering menu and made sure everything was correct there. I dont believe it is a fiber optic issue because I have light going in the amp and in Sirius receiver. Does anyone have any recommendations on what else to check? I have been without sound for 4 months and its driving me crazy. Thanks for any help you can provide.
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
those diagrams are showing just how complex this car's computer systems are, with multiple units interconnected with digital data busses (10 different CAN busses!) as well as fiber (Media Oriented System Transport, MOST). About the only way to diagnose this is to have the full XEntry Diagnostic System and dive into those data buses to see what is going on. The head unit A2 is connected to two different CAN busses for command and control, and 4 modules via the fiber MOST for actual audio. ALL this has to be working perfectly for this system to operate.
MBWorld Fanatic!
Joined: Dec 2020
Posts: 2,411
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From: 122W, 37N
2016 E350 4Matic wagon, 2019 Ford Expedition, 2019 Chevy Bolt EV
have a mechanic hook the car up to the XEntry Diagnostic system and read any and all codes associated with the media system. Said mechanic should have access to the wiring diagrams in WIS (I sure don't have that), without wiring diagrams its impossible to diagnose stuff like this.
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'11 E350, '11 E550, '98 M3, '95 E320
As its been alluded, it's not as simple as power and ground... though I guess if could be if one of those was the issue. With any module your diagnoses usually does the following:
- Scanning for codes and review live data
- Running built-in tests (if available)
- Check for power and ground (could be multiple) at module
- Verifying CAN
- Ideally with scope, otherwise is some form of continuity, resistance and "average" signal voltage
Last edited by bmwpowere36m3; Feb 11, 2021 at 01:06 PM.
