Head unit "system unavailible" then shuts off
Thread Starter
Member
Joined: Dec 2008
Posts: 202
Likes: 3
From: San Diego, CA
W202 C55 (5.4 swapped C43)
Head unit "system unavailible" then shuts off
Hey guys as the title says, audio worked fine for about a week after I purchased the car then one day while driving it just stopped playing, ever since then if I turn on the head unit, it displays the mercedes logo and warning message and goes to the regular menu, about 15-30 seconds later a message pops up saying "system unavailable" and shuts off.
I've tried disconnecting the battery for 20 minutes but nothing changed.
Any recommendations on how to troubleshoot the problem?
I've read if anything in the fiber optic loop has gone bad the entire system will stop working, would using a fiber optic loop bypass help diagnose the bad part?
And also as far a replacing the amp, audio gateway etc will a unit out of a W220 S class work?
Thanks!
I've tried disconnecting the battery for 20 minutes but nothing changed.
Any recommendations on how to troubleshoot the problem?
I've read if anything in the fiber optic loop has gone bad the entire system will stop working, would using a fiber optic loop bypass help diagnose the bad part?
And also as far a replacing the amp, audio gateway etc will a unit out of a W220 S class work?
Thanks!
MBWorld Fanatic!
Joined: Aug 2013
Posts: 1,077
Likes: 80
From: Anchorage
05 CL65
Mine has done that a few times over the 4 years I've had my car. Always just went away after a few drive cycles and started to function normally again. I never tried to figure it out because it always started working again before I got a chance to try and figure it out. Very annoying when it has happened. Hopefully yours goes away on it's own too if v8mercedes trick to reboot it doesn't work.
Member
Joined: Sep 2016
Posts: 221
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Mercedes S550 Coupe (now) CL55 (until last March 3), Ferrari 612, Porsche Macan GTS
I have a similar experience to Dr. Matt with my CL55. It will just shut down and then reboot after a few drive cycles and go away. It will happen a couple of times a year and is annoying but not earth shattering.
When i bought the car about 10 years ago it was still under warranty. The Mercedes dealer said it was a known problem but there were no known fixes (hate dealers). I assume that is still the case.
Hopefully i can remember V8mercedes solution and will try it the next time it occurs. That would be a great solution rather than waiting a drive cycle, but i can live with it if it doesnt. The key, over 10 years, it has not gotten any better or any worse.
So it is an issue but not a killer.
When i bought the car about 10 years ago it was still under warranty. The Mercedes dealer said it was a known problem but there were no known fixes (hate dealers). I assume that is still the case.
Hopefully i can remember V8mercedes solution and will try it the next time it occurs. That would be a great solution rather than waiting a drive cycle, but i can live with it if it doesnt. The key, over 10 years, it has not gotten any better or any worse.
So it is an issue but not a killer.
Thread Starter
Member
Joined: Dec 2008
Posts: 202
Likes: 3
From: San Diego, CA
W202 C55 (5.4 swapped C43)
Still been dealing with this issue for months now,
I'm just about at the point of buying all new speakers/amps/head unit and bypassing the entire system all together.
I've ordered multiple of the fiber optic bypasses from the Mercedes Benz dealership, I've bypassed my cd changer, Nav and what im assuming to either be the audio gateway or phone ( underneath the cd and nav, next to amp) as well as the amp even with everything bypassed at the same time the head unit loads up, now stays on longer than before, no sound very laggy and then "system unavailable" and shuts off. Also tried a battery reset with the bypass and nothing.
Any more ideas or help would be greatly appreciated.
is there a phone to bypass under the rear seat? found a Motorola box under passenger rear but no fiber optics leading to it.
Thanks -Dom
I'm just about at the point of buying all new speakers/amps/head unit and bypassing the entire system all together.
I've ordered multiple of the fiber optic bypasses from the Mercedes Benz dealership, I've bypassed my cd changer, Nav and what im assuming to either be the audio gateway or phone ( underneath the cd and nav, next to amp) as well as the amp even with everything bypassed at the same time the head unit loads up, now stays on longer than before, no sound very laggy and then "system unavailable" and shuts off. Also tried a battery reset with the bypass and nothing.
Any more ideas or help would be greatly appreciated.
is there a phone to bypass under the rear seat? found a Motorola box under passenger rear but no fiber optics leading to it.
Thanks -Dom
MBWorld Fanatic!
Joined: Mar 2006
Posts: 4,005
Likes: 711
From: ATLANTA
R Nine T
Same here. So in the driver side rear fender, there's about 8500$ worth of electronics. I first noticed a problem when stereo lacked punch and then one day dead.
So this is the deal, all of the electronics are above the wheel and are supposedly protected by the wheel well. It's a terrible two piece design that's RIVETED together. So water got in and destroyed everything as the tube in well was clogged.
What made it worse is my car warranty declined coverage and then my car insurance declined as it was declared a design defect. I was fortunate that my service advisor convinced them I could not have prevented tube blockage ( and I was ready to litigate
, and they relented. All components were replaced and both wheel wells were sealed.
I encourage all of you to check that area.
So this is the deal, all of the electronics are above the wheel and are supposedly protected by the wheel well. It's a terrible two piece design that's RIVETED together. So water got in and destroyed everything as the tube in well was clogged.
What made it worse is my car warranty declined coverage and then my car insurance declined as it was declared a design defect. I was fortunate that my service advisor convinced them I could not have prevented tube blockage ( and I was ready to litigate
, and they relented. All components were replaced and both wheel wells were sealed. I encourage all of you to check that area.
