Follow mercupgrades on Twitter

Please select country!!

Created: 8 Aug 2007

Last Updated: 16 Nov 2019

Lots of questions and answers about Mercedes Phone systems - techical and non technical.

Questions:

1 What is UHI or MHI ?
2 Whats the difference between UHI and MHI ?
3 How can I use Bluetooth with my Nokia 6xxx system ?
4 Is there a cradle available for my XXX phone ?
5 I want a bluetooth cradle, but theres lots of different ones. Which should I buy.
6 Where can I buy the cradle I need ?
7 Can I upgrade my old system to a UHI system ?
8 When I plug my Nokia 6310i into my pre 2004 car, it doesnt work ?
9 What are the part numbers for the phone controllers ?
10 I want to change my older Nokia system to the 6310i version, how do I do it?
11 The speed dialing function via COMAND picks random numbers to dial.
12 Why don't all my phone book entries make it into COMAND ?
13 Why is the mobile operator name different on phone and car ?
14 Why doesn't the car system ring with my Nokia phone.
15 Are the phones special, or will any one work?
16 Is my Bluetooth cradle SAP or HFP ?
17 How do I pair a phone to the HFP cradle?
18 How do I pair a phone to the SAP cradle?
19 Can I change the ring tone that I hear when using Bluetooth.

Answers:

1. What is UHI or MHI ?
UHI and MHI is the Mercedes phone system where you can change the cradle that the handset sits in just by sliding it out and replacing it with a cradle suitable for your phone or a bluetooth cradle.

2. Whats the difference between UHI and MHI ?
MHI is used in USA, UHI in the rest of the world. I've tried various MHI cradles on UHI systems and vice-versa and they seem to work. The control unit is a different part number, but the wiring and other parts seem to be the same

3. How can I use Bluetooth with my Nokia 6xxx system ?
Theres a device that can plug into the existing cradle and the car thinks that it is a Nokia 6110/6210/6310i and it then connects to your phone using bluetooth. Its caleld Visee0 MBU3000 (the old version is the MBU1000) but it is no longer found. Have a look on .

4. Is there a cradle available for my XXX phone ?
Here is a document describing both current and older cradles (often available on ebay). Mercedes UHI and MHI Phone Cradles

5. I want a bluetooth cradle, but theres lots of different ones. Which should I buy.
Mercedes Bluetooth cradles use two bluetooth technologies. (a) Headset profile (hands free HFP)- this is like a normal headset (b) Sim Access Profile (SAP), in this case the cradle acts as a phone and borrows the ID from the SIM in your phone. The SAP cradle has the benefit that car's aerial is used, but there are few mamafacturers that support SAP (Nokia does on most new phones). There are 2 Bluetooth HFP cradles in the USA, V1 and V2.
There is 1 Bluetooth HFP cradie for Europe, although there have been a few versions.
There are 2 types of SAP cradle, one which has a handset that can be picked up for a private conversation, and one that doesnt. And there is an old, and a V2 version of both of those. Part numbers are in my UHI phone cradle document mentioned above.

6. Where can I buy the cradle I need ?
The Mercedes HFP is no longer available new, but you can purchase warranted / tested / software-updated used ones from Comand Online shop. You can also order cradles straight from your dealer, and there are plenty on ebay. If you use the link Ebay Cradle Search it will search for cradles in German as-well as the rest of English which will save you money.

7. Can I upgrade my old system to a UHI system ?
MB dealers will not do this for you, but it can be done. Contact me via this website tell me where you are and I may be able to suggest who can do it for you

8. When I plug my Nokia 6310i into my pre 2004 car, it doesnt work ?
The phone control unit probably needs upgrading to support that phone. There have been different releases of phone control unit, each one supporting new Nokia phones in the 51xx/61xx/6210/6210i/6310/6310i range.

9. What are the part numbers for the phone controllers ?
For cars with CD based COMAND systems ("D2B") - portable phone (options 273.317,852,854)
A230 820 42 26 - UHI system
A230 820 51 85 - Nokia 6310/6310i
A203 820 25 85 - Nokia 6310/6310i, replaced by 203 820 51 85
A203 820 99 26 - Nokia 6210i and before
A203 820 32 26 - Nokia 6150/6110/5110
A220 820 57 26 - Nokia 3110
A210 820 57 26 - Nokia 3110 replaced by above
A220 820 09 85 - ???
A220 820 67 26 - ???
A220 820 00 26 - ???
A220 820 01 85 - Nokia 3110 with dynamic route guidance (Germany) (option 815)


For cars with DVD based COMAND ("Most") - portable phone (option 380,382) A211 820 58 85 - Nokia 6310/6310i
A211 870 24 26 - ???
A211 820 64 85 - replaced by above


10. I want to change my older Nokia system to the 6310i version, how do I do it?
You need to buy the Nokia 6310i phone control unit (see above). Its a simple swop out, its either in boot/trunk on left behind interior and external wing (W208/W210), in control box under boot/trunk carpet by rear seat (W203/W209), under right hand seat (W163) or under back seat (W220/W215).
If you have the Nokia 3110 system, then you will need to change the whole cradle, I suggest using the most modern version - which is shown in my ML phones document as the "curvey" cradle. The part numbers differ depending which car they are going in because of the length of the cradle and you'll need some screws/bungs as-well - but it is plug and play.
If you have the rectangular cradle without a clip that holds the phone in at the top, then you need to add an adapter, part number A203 820 07 51 - theres a picture of the cradle in the ML phone document.
Mercedes recommend that if you have the curvey cradle for the 6210i that you replace the cradle with the correct part for the 6310i as the phone can fall out - not so much of a problem if the cradle is horizontal, but if its upright i'd replace it.

11. The speed dialing function via COMAND picks random numbers to dial.
The COMAND uses the 1st 10 numbers from the SIM as the 10 numbers available for speed dialing - most phones allow you to chose the numbers to use for their speed dial function. So you have to put the numbers in the 1st 10 SIM memories - please refer to your phone's handbook - its often far from trivial.
If you have the UHI system and COMAND-APS (DVD based) from about model year 2005 there is a bug in the phone module that causes it not to use the 1st 10 SIM memories, the dealer can flash the UHI phone module using their star diagnosis computer with a special adapter.

12. Why don't all my phone book entries make it into COMAND ?
There are a number of issues that cause this to happen
a) Where a phone has multiple numbers per contact, you normally only get the default number loaded. If you are using bluetooth SAP V2 adapter and latest Nokia smart phones (i.e N series) then this works a bit better and you get multiple numbers loaded
b) Particularly on COMAND 2 (CD based) cars, a block of numbers is reserved for SIM entries, the block is the same size as the SIM memory (on current SIMs thats 200) and the phone system can only hold 256 - so you only end up with 56 memories to use.
c) Some phones, only SIM memories can be downloaded and not phone memories
d) When using bluetooth some phone types work well, others don't at all. Look at the compatability list in the UHI cradle document mentioned above.
If you have a non bluetooth cradle, the only answer is to put your contacts in the SIM that you want to use in the car (and perhaps set the phone handset itself to only use it's memory, so when you use the phone itself you don't see the SIM contacts, when you use it in the car you do see the SIM contacts).

13. Why is the mobile operator name different on phone and car ?
The actual phone network/sim has a number for each operator. The phone system has a list of names and numbers in its software. So, if the operator changes it's name (because its sold, or because it wants to!) then the list in the phone software is out of date. So the phone software in the car and the phone software in the phone can have different names for an operator and thus the displays will be different.

14. Why doesn't the car system ring with my Nokia phone.
When most Nokia phones are used, the phone is switched to 'hands free' profile. If the 'hands free' profile ring setting is set on silent/quiet then the rining in the car will be off or quiet. Adjust the ring setting / tone whilst the phone is in the cradle.

15. Are the phones special, or will any one work?
In Europe, MB have always used standard phones so you can just buy the approprate phone from eBay, phone shop etc. In the USA the Motorola phones have had special software, so only a Mercedes handset will do.

16. Is my Bluetooth cradle SAP or HFP ?
There are 2 cradles technologies, HFP and SAP. The SAP cradle is only for Europe. If the cradle is black about 10cm x 6cm then it is HFP. If its silver and shiny, slide of the cover at the bottom of the front, if there is a SIM holder in there, it is SAP Version 1 or Version 2, otherwise it is the USA HFP cradle.

17. How do I pair a phone to the HFP cradle?
Hold down the button on the HFP cradle for about 5-10 seconds until the blue light flashes rapidly. The button is the mercedes star (USA system), or the bluetooth sign (Europe etc). Then tell your phone to search for bluetooth devices, it will find MB Phone System, tell it to pair - the code is 62872.
Ensure you set the pairing in the phone to 'trusted' or 'automatically pair'.

18. How do I pair a phone to the SAP cradle?
Turn on bluetooth on the phone, and if there is a menu item to enable SAP (or Remote Sim Access, or similar) ensure that is on, and that the phone is visible. Put the COMAND or Audio system onto 'Telephone' menu.
Press the mercedes Star button on the SAP cradle (or in the case of the handset version, push the button on the side) for about 5-10 seconds unitl the blue light starts flashing rapidly. The cradle is searching for devices in range. After a while, the audio system screen will look like it is connected - look in the call history and you will find your phone there, press the call button to make a call to it, and a 16 digit (8 pairs of 2 digits) will be displayed on the audio system. Wait for the phone to ask for the pass code, then enter the 16 digits. Now you will hear a rising tone (success), wait until the system pairs again with the phone.
You must now tell the cradle to download the phonebook, do this by dialing 0000 on the Comand/Audio keypad, the connection will drop, the phonebook download happens (can take a while), and the connection will be re-established.
Ensure you set the pairing in the phone to 'trusted' or 'automatically pair'.

19. Can I change the ring tone that I hear when using Bluetooth.
On the HFP cradle the ring tone comes from the phone, so you can just change it. On Nokia phones the tone is associated with the profile, which will be headset when using the HFP cradle. On SAP cradles you can not change the ring tone.


If you found this information useful, please support the site by making a donation via Paypal. Any amount at all helps me improve the information on the site.



Comand Online Ltd - the place to buy Mercedes iPod kits, phone kits, retrofit parts & map disks



Comand Online

MY AUTOCAR - THE BEST PLACE TO TALK CARS