Command knob totally non functional

[PeteDawson63]

Hi all,
I have a C200 (2012) with a non responsive command knob.
So far. I have bought a spare and connected this at the point under the gear stick area and also had the radio out to check for a disconnect.
There are no obvious problems to see and I was wondering if it's possible to have the radio working and responding to the buttons on the panel but not at all to the command knob? Could it be the radio unit needs to be replaced?
Any suggestions will be much appreciated.
Pete

 

[Deleted member 166430]

Check out fuse 11 in the box under the bonnet on the rhs as you look at the car. This is the fuse for COMAND.

 

[PeteDawson63]

Thanks very much for that tip.
Would have been nice and easy If It had been the fuse, but unfortunately It looks ok.
Cheers,

 

[Deleted member 166430]

Thanks very much for that tip.
Would have been nice and easy If It had been the fuse, but unfortunately It looks ok.
Cheers,

That's a shame. Sounds as though it's going to be one of those laborious jobs of checking the continuity of all the wiring to the control knob. I would have thought it was perfectly feasible for the radio to be working and responding to its buttons while the COMAND knob does nothing. Sorry, I can't be any more help.

Good luck.

 

[PeteDawson63]

That's a shame. Sounds as though it's going to be one of those laborious jobs of checking the continuity of all the wiring to the control knob. I would have thought it was perfectly feasible for the radio to be working and responding to its buttons while the COMAND knob does nothing. Sorry, I can't be any more help.

Good luck.

No, please don't apologise. You really you have been a great help.
It would seem it may be worth buying a second hand one to try out given that info. But I will see if there's anywhere around here that could test it first.
Thanks again.

 

[Deleted member 166430]

You're welcome.

The only common problem with the control knob that I'm aware of is the plastic shaft breaking. But you can feel that when it spins around without achieving anything. it should be easy enough to test that the control knob is doing what it should by probing around on its connectors with a multimeter. You don't need to know values, just to see that things change when you rotate the knob.

 

[Chrishazle]

If the plastic shaft is broken, it's only the rotational aspects of the control knob that do not work, the functions operated by pushing the control knob back and forward or side to side still work (or at least did when mine broke!).
This may help : comand knob repair youtube - Căutare Google

 

[PeteDawson63]

You're welcome.

The only common problem with the control knob that I'm aware of is the plastic shaft breaking. But you can feel that when it spins around without achieving anything. it should be easy enough to test that the control knob is doing what it should by probing around on its connectors with a multimeter. You don't need to know values, just to see that things change when you rotate the knob.

Thanks for that.
I was aware of this problem and have seen a few threads on it here on the forum.
It's not that in my case. Nothing on the command knob works at all. I also tried a spare knob with the same result.
Cheers,
Pete

 

[PeteDawson63]

If the plastic shaft is broken, it's only the rotational aspects of the control knob that do not work, the functions operated by pushing the control knob back and forward or side to side still work (or at least did when mine broke!).
This may help : comand knob repair youtube - Căutare Google

Thanks for that. Much appreciated