Parasitic draw and no sound - CL 500

[Parkheadlad]

Hello. As advised by very helpful members I have copied and pasted my discussion (see below) from a previous thread (yesterday) but this time with a more eye catching heading. As suggested I have attached photos of the audio console and the set up in the boot and also photos of the amplifier, navigation system and the CD changer. As mentioned below I receive no sound at all from the radio and the CD player (including the single CD slot at the audio console unit).
With regards the parasitic draw, the reading at the battery is 0.28A. annoyingly this can change - the other day it was 1.87A and kept fluctuating between 0.7 and 1.87A. I have tracked the draw down to two fuses - the main culprit being the fuse that feeds the right hand front door controls ( see photo) - it is drawing 0.11A. No idea how to rectify this problem.
As mentioned below, any guidance would be appreciated.


I bought a CL 500 early 2004 model and it came with a couple of problems.
It has no sound (which I knew about when I bought the car) and I have tried a couple of things to source the problem. I suspect the fault lies in the boot where the CD changer, navigation, radio and amplifier are located. I have tried using a Fibre Optic Loop Cable Bypass Connector between each device but no joy ( could be using it incorrectly). Is there any way to test each device separately to locate the fault? I am assuming the dashboard audio unit is not the culprit.....could be wrong.
I have also been plagued with a parasitic draw from the battery and I have removed the negative battery terminal connector every time I park the car for the last 6 months! I have narrowed it down to a couple of fuses and I suppose I need a tech to sort the problem.....wondering if anybody knows of a MB specialist in the West Cumbria area?
Any advice would be gratefully received!

 

[Botus]

I was thinking with the picture - this must be one of the last later units (indeed orange fibre optics would suggest its the later MOST circuit not the crazed early one)

It looks like a NTG1 ? possibly a CD auto-changer buried in the dash under a flap? this might be dead and could be looped out?

And then the unit in the back might be a Nav unit in the boot ?

Strangely the picture in the boot looks like there's a very similar unit to that used on the later 221? they use a TTU (tuner and amp combined) - and on these they age and the main fault is NO sound - and on the 221 this is an integral part of the basic system - so you can't loop it out or the whole system stops and now as it looks like an NTG1 it says in the data in the post below - it has a unit that integrates the tuner and amp as well

can you get that part number from that silver module in the boot and post the info from it (should be a white sticker saying what it is and what hardware / software etc.) ?

 

[Botus]

from that link I gave http://www.mercupgrades.com/COMAND+++All+about+the+different+Mercedes+COMAND+systems-article-54.html


the NTG1 was introduced into the W220 S class and W215 CL class for Model Year 2004, the R230 SL for Model Year 2005 and the SLK from launch

it was the first DVD based system, and thus the map disk carries a whole region (for instance Europe) on a single DVD.

The MOST system (and thus the NTG1 system consisted of 3 separate devices, the AGW (Audio Gateway), the head unit (COMAND) and the navigation processor. The AGW contains the FM/AM tuner(s) and the amplifier, the MOST bus master controller and the diagnostic gateway for diagnosis and configuration.

The telephone system. voice recognition, CD changer, Harmon Karden premium sound system and TV tuners also connect to the MOST bus to route audio in/out of the system. In the case of the HK sound system, the HK amplifer contains the AGW and replaces the standard AGW.

The navigation processor is always in the boot (trunk) of the car, and the AGW is also often hidden in the boot of the car or under passenger feet in the SLK.

NTG1 was fitted up until Model Year 2009 in the W220 S, W215 CL, R230 SL, W211 E, W219 CLS, R171 SLK vehicles.

The NTG1 head unit (COMAND) can play DVD and MP3 loaded CD/DVDs also.

Most parts of the NTG1 system are made by Becker (for European vehicles). However, in the S/CL/SLK/SL it is made by Siemens (and North American systems are made by Siemens).

The W211 E, W219 CLS, R171 SLK have auxilary audio inputs but the W220 S, W215 CL, R30 SL do not and thus the Mercedes iPod interface will not work in the S/CL/SL.

The NTG1 uses proprietary map disks, which although the maps are made by Teleatas and Navteq have to be supplied via Mercedes benz. Mercedes use a coloured flash on their map disk packaging, NTG1 disks have a Green stripe. Currently the map disks only support 5 digit post codes in the UK.

 

[Parkheadlad]

I was thinking with the picture - this must be one of the last later units (indeed orange fibre optics would suggest its the later MOST circuit not the crazed early one)

It looks like a NTG1 ? possibly a CD auto-changer buried in the dash under a flap? this might be dead and could be looped out?

And then the unit in the back might be a Nav unit in the boot ?

Strangely the picture in the boot looks like there's a very similar unit to that used on the later 221? they use a TTU (tuner and amp combined) - and on these they age and the main fault is NO sound - and on the 221 this is an integral part of the basic system - so you can't loop it out or the whole system stops and now as it looks like an NTG1 it says in the data in the post below - it has a unit that integrates the tuner and amp as well

can you get that part number from that silver module in the boot and post the info from it (should be a white sticker saying what it is and what hardware / software etc.) ?

Thanks for the information. I'll try to remove the module this weekend - out of interest, what exactly is the silver module?

 

[Botus]

well now I guess its the AGW (audio gateway), if it does what I think it does its the same thing my car has, but on mine its called the TTU and on the HK system its called the TUA

both the TTU and TUA on the S class W221 and CL216 fail like clockwork, and the fault is always no sound (it progressively becomes randomly intermittent till 6 months on there is no noise anywhere) but everything else functions perfectly aside from the channel numbers from the radio vanish from view. A non broken amp is plug and play and everything just works again. But I'd never read that happens on other systems

 

[Parkheadlad]

well now I guess its the AGW (audio gateway), if it does what I think it does its the same thing my car has, but on mine its called the TTU and on the HK system its called the TUA

both the TTU and TUA on the S class W221 and CL216 fail like clockwork, and the fault is always no sound (it progressively becomes randomly intermittent till 6 months on there is no noise anywhere) but everything else functions perfectly aside from the channel numbers from the radio vanish from view. A non broken amp is plug and play and everything just works again. But I'd never read that happens on other systems

Thanks Botus. I bought the car with no sound so unable to say if the no sound was gradual over time. Nothing works at all - a wee clue may be the digital clock reading is all over the place - read somewhere it is controlled by the Navigation unit.

 

[Botus]

If the time comes from a link to satellites - then its probably unfixable to work as intended - but quite likely you can flip from auto to manual input and just sort it each time we get daylight saving

satellites used to run on a 19 year clock system (as most ran out of fuel before that and fell out of the sky), so had a simple nasty calc inside on how to do time and dates. Newer ones get better maths, but the old one's rotate their brain in this 19 year madness and went back to year 0 in April 2019. So you car is looking to understand information about time old satellites no longer send out.

Clever people could rip an update CD and swap the info on the file that programmes your car on how to tell the time - but its not as easy as you'd hope. On old tomtom devices its out there to add a few lines of code, an American guy sorted the later CL and Merc did some of their later cars

GPS week number rollover - Wikipedia

en.wikipedia.org

 

[Naraic]

Is it a Bose system? If yes...it'll be the amp.

 

[Parkheadlad]

If the time comes from a link to satellites - then its probably unfixable to work as intended - but quite likely you can flip from auto to manual input and just sort it each time we get daylight saving

satellites used to run on a 19 year clock system (as most ran out of fuel before that and fell out of the sky), so had a simple nasty calc inside on how to do time and dates. Newer ones get better maths, but the old one's rotate their brain in this 19 year madness and went back to year 0 in April 2019. So you car is looking to understand information about time old satellites no longer send out.

Clever people could rip an update CD and swap the info on the file that programmes your car on how to tell the time - but its not as easy as you'd hope. On old tomtom devices its out there to add a few lines of code, an American guy sorted the later CL and Merc did some of their later cars

GPS week number rollover - Wikipedia

en.wikipedia.org

Can't work out how to revert to manual setting.......but at the moment it's the least of my worries.

 

[Botus]

it might be buried in dealer tool coding options - I'm not an expert on these - funny enough my father's has NTG1 and his clock has always been manual - but I read the same cars can be auto (and thus now wrong) - but his always worked (doing time via screen surround buttons) and other deeper stuff by wheel buttons by a nut job and confusing cluster choices - and now and then it decides its german