Audio 50 Loses Unlocked State After Successful Unlock

[waxxx]

I have a HU204 Audio 50 APS head unit, anti-theft protection is displayed. I entered the correct PIN code using Vediamo. It was successfully unlocked.
So when using Vediamo or DTS Monaco the PIN code is accepted and the coding is accepted BUT as soon as the car goes into sleep mode or after the ignition is turned off the anti-theft system is turned on again, or when the head unit is restarted with the HardReset function, it loses its unlocked state and the anti-theft system screen appears again.
In this case, HU loses all stations, language settings coded in the unlocked state, and then the security code appears again.
Does anyone know how to fix this? The car is a W212.
Any ideas what's wrong with it?

 

[Filip]

Hi, unfortunately I have no idea how to fix this, I have the same one somewhere + Bluetooth doesn't find the phone anymore.
This is a little known defect, some companies offer to fix this problem, but the cost is very high, it is cheaper to replace.

Maybe it's better to get Audio 20, as it's plug and play and supports Bluetooth Audio. Or upgrade to COMAND.

 

[waxxx]

Thanks for the reply. So you mean that buying an Audio 20 unit (what NTG level is that and what is the correct MB part number?) should be a plug and play replacement/retrofit process? Doesn't Audio 20 require some coding to work properly?

 

[Filip]

I had one with part number A 212 870 00 89.
This is plug and play, both NTG4. They look the same, but the Audio 20 lacks the Navi button.
You may need to activate Bluetooth Audio using Vediamo.

 

[ivomarchev]

I had a similar problem with X164, the problem was in EIZ, VIN number was not saved, I entered VIN and the problem was solved.

 

[bigchevy66]

As ivomarchev said, make sure the EIS is programmed with the correct VIN. This was a very common issue on the 164 chassis and MB had technical bulletins about it.