No power to phone cradle

[IAmKloot]

I hope this hasn't been done to death - I did search, but didn't find what I was looking for...

I have a 6310i phone cradle in my 2004 W211, which has a curly cord. It has a Viseeo MBU-1000 fitted, which all tallies with the information I've found here and elsewhere in terms of cradles, microswitches and curly wire being connected at the other end.

However, try as I might, I can't get any life at all from the MBU-1000.

I plugged it in to an old Nokia charger (as advised) and it lit up like a Christmas tree, so clearly it is not getting power in the cradle.
As I understand it, the cradles are notorious for poor connections, but having cleaned all of them carefully, I'm still getting nothing. Is there a tip for improving the connections?

Also, is there a dedicated fuse for the cradle? If so, where-oh-where can I find it? I've found the fusebox in the end of the dash and the one in the boot, but nothing on the folded up sheet tells me which fuse is the one for the phone.
Is there a separate in-line fuse?

Any help would be much appreciated.

 

[Diesel Benz]

Have you checked if the phone control unit is still present and connected to the fibre ring? Power to the cradle comes via the control unit, check that fuse too.

 

[IAmKloot]

Thanks DB. I'm not clear what you mean by that? What would the control unit fuse be called?I found the fuse for the phone (under the bonnet, location f55...), but it's inperfect condition.

 

[IAmKloot]

I checked with a multimeter and there is no power coming from the relevant terminals on the cradle. It's either switched off, not connected or a fuse somewhere has blown...

 

[Vilus]

The connections in the armrest are easy enough to check. The cradle is fixed in the top armrest with the split lid with T8 torx screws. There is a connector underneath. The curly cable then goes down inside the cubby hole of the armrest. If you lift the felt on the bottom you will see two slots in the middle edge of the base. Slide a flat screwdriver in and lift the bottom of the armrest cubbyhole up. There should be a connector from the wiring loom. If they are secure then it is not just a loose connection.

The telematics work on a fibre optic MOST ring. If any component in the ring is faullty then the whole loop is down. On vehicles with COMAND the loop includes the dash headunit, Audio Gateway/amplifier, CD changer, SATNAV, telephone control unit, Microphone control unit. I'm not sure on Audio20/50 fitments. As mentioned the cradle gets its power from the Telephone control unit. You could get the vehicle put on STAR diagnostics by a Mercedes specialist. STAR will give you a fault code along the lines of ' error on the MOST ring at position xx. ' This corresponds to one of the components mentioned above which is causing a fault. If you have COMAND then you should find that the whole system will not boot up if there is a faulty component. You will get the MB splash screen then it will switch off. Again with AUDIO 20/50 fitment I'm not sure.

The Telephone control unit, and the microphone control unit are located in the boot, under the metal cover which runs behind the back seat between the wheel arches on the saloon. It may be different on the S211 estate. When it is all up and working you will see Viseeo displayed in the speedo display on the dashboard.

Mine stopped working due to a faulty microphone controller and there was no power to the cradle. As soon as the module was replaced it all sprang back to life.

My regular MB specialist couldn't find the fault so I took it to Richard and Alfie at COMANDONLINE. They diagnosed and fixed the problem in minutes!

 

[IAmKloot]

Thanks Vilus, that is excellent information. For the convenience of estate owners, the Nokia control module, the hands free controller and dual band compensator module are located under a separate piece of floor that is only accessible with the rear seat backs folded forward. It's a full-width, carpeted panel about a foot wide that butts up against the hinged edge of the trap door to the spare wheel. It is held in place by two clips at the front and then slides out forwards. Under this is a layer of insulation, then the three units are revealed. Took me ages to find it!