SL350 (facelift) Comand NTG2.5 replacement

[edwaado]

This is a SL350 R230 facelift model with the Comand NTG2.5 (it has the SD reader slot), which I'm attempting to replace with an Alpine unit.

I bought ISO adapters and steering wheel interface recommended by dynamicsounds - Connects2 CTKMB08 - Mercedes SL R230 2004 - 2014 Double Din Car Stereo Fitting Kit
And this is me testing the harness.

The issue appears that the ground and 12v are switched in the connect block. In the attached pics I'm showing a reading from three of the pins on the ISO adapter.

Yellow - shows 12v, which looks correct as this should be the permanent 12v
Black - shows 12v confused which should be ground
Red - shows practically zero (4.7mv) which should be 12v when ignition is on (I think).

I've contacted dynamicsounds with this info for support, but wondered if I'd done something obviously wrong that you guys might be able to see.

Also, I discovered this _after_ connecting everything together and discovering that the head unit wasn't working. Imagine my alarm at finding that the metal casing of the head unit was 12v :-/
This kit is plug and play, so really don't know why it would do this unless there is a fault in the manufacturing.

Thanks
Ed

 

[NJSS]

Welcome Edwaado

Good luck.

NJSS

 

[edwaado]

This is a SL350 R230 facelift model with the Comand NTG2.5 (it has the SD reader slot), which I'm attempting to replace with an Alpine unit.

I bought ISO adapters and steering wheel interface recommended by dynamicsounds - Connects2 CTKMB08 - Mercedes SL R230 2004 - 2014 Double Din Car Stereo Fitting Kit
And this is me testing the harness.

The issue appears that the ground and 12v are switched in the connect block. In the attached pics I'm showing a reading from three of the pins on the ISO adapter.

Yellow - shows 12v, which looks correct as this should be the permanent 12v
Black - shows 12v confused which should be ground
Red - shows practically zero (4.7mv) which should be 12v when ignition is on (I think).

I've contacted dynamicsounds with this info for support, but wondered if I'd done something obviously wrong that you guys might be able to see.

Also, I discovered this _after_ connecting everything together and discovering that the head unit wasn't working. Imagine my alarm at finding that the metal casing of the head unit was 12v :-/
This kit is plug and play, so really don't know why it would do this unless there is a fault in the manufacturing.

Thanks
Ed

Crap

On the left is the pinout diagram for R230 NTG2.5 on the right is the pinout diagram for SLK r171 Audio 20 system. They have the same connector block, but use different pins.
Specifically pins 15(gnd) & 16(+12) are power in the SLK and pins 12(gnd) & 15(12v) are power for RTG2.5

Despite purchasing the system for a Mercedes SL, I seem to have the connector for an SLK. I used to have an SLK and used the same connector system there, so I actually have a spare harness and connector.
I've used that to "fix" the connector pins, and now get GND and 12v constant, but the connects2 box isn't sending ACC12v (ignition key). This could be more faulty pins, or I could've blown the connects2 box; I really hope it didn't blow the head unit.

 

[edwaado]

Sorted it, will post pictures and update later once finished the install.

I had to cannibalise the old SLK quad connector to get 2 extra pins (from the main wide block), which I used to create pins for CAN BUS High and Low - relocating from the small thin pins. Moved the pins for GND and +12v permanent to correct position.

After a little bit of trial and error - I hadn't appreciated that the speaker pins were all wrong also - relocated the speaker pins, and then tested. Thankfully the head unit wasn't fried after giving it 12v on the GND, and it all fired up, and sounds awesome.

TL;DR - rewired/relocated pins based on the NTG2.5 pinout diagram, and it worked.

 

[edwaado]

Finished (for now) the installation.

As mentioned in the previous post, I had to repin the quad connector to match the r230 NTG2.5 pin out diagram. Once I did that the head unit worked. Unfortunately the steering controls do not work :-/

I've got an adapter for the GPS coming, so will add that then, and may install the DABs aerial.

The fascia doesn't fit into the hole - it's the right size for the dashboard, but the tabs are in the wrong place. This could be that Mercedes redesigned the tabs and slots when they facelifted the r230. To work around this I had to cut off tabs on the side and top, then I had to fashion a couple of new tabs on top to support the mounting screws. See the picture below (thank goodness this gets hidden!).



Obligatory peeling off the protective film



Boom! Works, sounds awesome!

 

[hedgehogsdad]

That looks great, well done on getting it to fit.

Looks like they don't do a kit for the 2003 year, only 2004 onwards....

 

[Gbrowncls55]

You are a braver man than I (or you have a masters in car electronics) Glad its all working well Interesting post.

 

[edwaado]

That looks great, well done on getting it to fit.

Looks like they don't do a kit for the 2003 year, only 2004 onwards....

this might help:

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[hedgehogsdad]

Looks good, although not as good as yours. They are probably too far away from me to work, I wonder if there is a similar firm in the North West??

 

[richard]

There are so few mods done to SL-R230 - particularly NTG2.5 units that most of the manufacturers get their kits wrong - The loom supplied in that kit (CTSMC004.2) is wrong - its for NTG1-Audio-20 in E class, CLS or SLK which has the power and speakers completely differently wired.

- The loom for a W169 NTG2.5 (MY2009 or later) will do the job

R

 

[hedgehogsdad]

There are so few mods done to SL-R230 - particularly NTG2.5 units that most of the manufacturers get their kits wrong - The loom supplied in that kit (CTSMC004.2) is wrong - its for NTG1-Audio-20 in E class, CLS or SLK which has the power and speakers completely differently wired.

- The loom for a W169 NTG2.5 (MY2009 or later) will do the job

R

Sorry, can I just check that I understand. Is that it will do the job for an '04 onwards car??

 

[richard]

Sorry, can I just check that I understand. Is that it will do the job for an '04 onwards car??

Nope. Only a my09 onwards (ie the mid 2008 facelift where NTG2.5 was installed). The Connects2 loom is no good for MY04-08 either as the tuner-amp is not at the front.