Comand MOST Problem B245
I have a B245 with a Comand NTG-2 ( I think ). I have a common problem whereby the Comand system times out on the Mercedes Logo and then goes off with nothing working. I took out the 6 CD changer in the glove box and disconnected the fibre link and noticed that there was no signal ( light ) coming into the connector, but the CD Changer was flashing a light from the unit connector.
So I'm guessing I have an optical failure somewhere in the ring. I have a MOST loop connector to bypass the individual units now but I am unsure how to locate and identify the units in the MOST loop and in what sequence to isolate them with the MOST Fibre loop connector.
I'm guessing but maybe the only two items I have external to the NTG-2 are the blue tooth phone unit in the centre armrest and the 6 CD changer in the glove box.
So - Sat Nav and audio may well be all in the NTG-2 but how do I prove that - can't loop out from the connector out of the NGT-2 because I have the male connector but would need a female for that.
If the 6 CD Changer is not receiving an optical signal then it seems to be either a cable failure to it, something prior to it in the MOST ring or nothing coming out of the NTG-2.
I am going to take out the NTG-2 and see if the connector is putting out a fibre signal.
Has anyone any advice or support for me in this effort please? Am I on the right approach?
Kind regards
Ken
The MOST ring was failing because the phone unit which is under the front passenger seat was damaged by water ingress to the foot well. As an initial work round I got a MOST ring loop bypass cable - off eBay for £13.00 which bypasses the faulty unit. I unplugged the fibre optic cable and plugged in the loop bypass cable and the system burst into life.
I took the phone unit apart and cleaned up the electronics but it is no more. It is late. It has gone to meet its maker.
I now need to find out how the water is getting in.
I think it is down to weather conditions - very heavy rain.
There seems to be lots of statements around sayingt how this can happen - will update when I find out in my case.
Ken
Here in UK we see them very often. We keep lots of spare phone controllers as a result. You can put them in a plastic bag when you replace it ...
R
I'm still getting water under the carpet into the passenger side seat leg location wells. I haven't driven it in the rain nor gone through any puddles so it must be getting in from above somewhere. I have towels under the carpets to soak up the excess and there isn't much there any more - but after the rain the last few days I have found water in the leg wells about 1/4" deep. The carpets and towels don't seem that wet.
I have hosed down the windscreen to check the drains at the front and they seem to be working ok. I have also just hosed down the rear offside light assembly to see if it is getting in there and running backwards.
Do you have any other ideas please?
Maybe this problem is only common on vehicles that have had their windscreen replaced.
PROBELM SOLVED
I have just had my windscreen replaced because on a hot day it cracked on it's own. There was no evidence of a leak when taking out the old windscreen by inspecting the sealant on the glass. However - the car has been dry ever since ( we've had a lot of rain )and I am now convinced that in my case the water ingress has been fixed by replacing the windscreen.
There may of course be other reasons water gets in but in my case I had looked at all the other suggestions and ruled them out leadingm me to the conclusion the window leak was a likely option.
This initially caused the phone unit located in a floor pan under the passenger seat ( RHD car in my case ) which I changed and fixed the fault. I left that on top of the carpet under the seat to keep it dry as water was still getting in.
Since then I have a few other spurious problems that I relate to water ingress which hopefully I can now fix. These include a "rear passnger door open" warning on all the time, rear parking alert in the top of the rear screen not working and also the doors not automatically locking when moving off.
I suspect the SAM module but as yet I am not certain where it is - B200 W245 Right Hand Drive - .
Any advice on the location would be very helpful.
Ken
Last edited by Kenny Rich; Sep 14, 2020 at 12:08 PM. Reason: Problem solved







