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Audi Bluetooth Low vs. Bluetooth High and related topics explained A4 B8/A5/A6/A8/Q5/Q7 (by LoCal)

30.3.2009 (updated 21.2.2010) - The following is a collection of postings by LoCal (and associated links) explaining the difference between basic Bluetooth phone-prep (or Bluetooth Low/phone-prep low in some markets) in Audi A4 B8/A5/A6/A8/Q5/Q7 and the SIM Access Profile phone (or Bluetooth High in some markets). Published with permission.

There are generally four levels of factory phone support in the above-mentioned models. Some history and handset options vary between models, but generally:

1) The low option, also known as the phone-prep (short for phone preparation), a phone-prep with cradle connector in/under front armrest for physically connecting a phone with an optional cradle (to connect an Audi phone-model-specific adapter into) and a roof antenna (in the GPS shark-fin). Note: The roof-antenna is only used through the cradle, when a phone is connected via an adapter there - it is also charged when there. Alternatively phone can be connected wirelessly via Bluetooth hands-free audio, but in this mode the roof antenna in the car is not used - only the phone's own antenna.

For the low option, there is an Audi SIM Access Profile accessory that attaches to the cradle and provides some of the features of the high option, allowing use of the roof aerial through the Bluetooth SAP profile via Bluetooth, when used with a compatible phone. (But it does not allow reading SMS from the MMI screen unlike the high option.) For part numbers etc. see below.

2) The Bluetooth only, a version of the low option. Audi ships a version of the above-described system without the cradle and the aerial (so called Bluetooth only), which is useful for only the Bluetooth hands-free mode. That mode always uses the phone's own antenna only, so no external aerial is needed. The Audi SIM Access Profile accessory adapter mentioned above can not be used with this system because of the lack of a cradle and aerial.

3) The high option, also known as Bluetooth SAP phone, a SIM Access Profile mobile phone integrated in the car (by default it has no visible handset) which uses Bluetooth to download SIM card data from a compatible mobile phone and then uses the cars roof antenna and phone module for the actual mobile business. Benefits are better quality because no audio goes via Bluetooth and because the roof antenna is used for better reception. Also allows reading SMS from SIM card on the MMI screen. This system can be used as a traditional Bluetooth hands-free audio system as well, if so configured by the user. There is no cradle connector in this option and your mobile phone is never physically connected to the system. In MMI 3G, a SIM card can also physically be attached to the car and thus the system can work without a Bluetooth connected mobile phone.

4) High option with handset. Same as previous, except adds a convenience handset to the car which can be used to talk, send SMS etc. This is the only current Audi system that allows sending SMSes via the car's own equipment (also the regular high option does allow reading them on the MMI screen though). Allows also physically connecting a SIM card (both MMI 2G/3G) for use without a separate mobile phone connected via Bluetooth.

Assorted messages and links below for further details.

Bluetooth Help

"Just a note: Laingy did not specify if his/her car has the Bluetooth handsfree/phone-prep only, or if he has the SIM Access Profile Bluetooth system Deepmeister is referring to. Both can be used in normal BT HF mode, latter also in SIM Access Profile mode that requires more fiddling and the longer PIN code (since it transfers SIM access data)...

Generally, I think U.S. cars come without SIM Access Profile (just me recollection, could be wrong), in Europe cars with navigation with SIM Access Profile and cars without navigation without SIM Access Profile. But there may be differences in accessory options...

But, yeah, I agree, there is a time limit from start of car with the pairing. Make sure both car and phone are set as Bluetooth visible in the settings too. And read the respective manuals."


MMI upgrade to 5570

"BT low users can add the official Audi SAP accessory to their phone cradle.

Part 8P0 051 440 if I have it correctly.

And no matter the phone type, SIM Access Profile currently allows only reading SMS messages in the SIM card! Not in the phone. So, it is of limited use. But you can use it to read messages that arrive to the phone during driving, which is useful."

"My experience with SAP is good. I hate the way Bluetooth HF sometimes is vulnerable to interference, SAP works great all the time.

HAWKiS5 is right about the fact that using SAP will shut down your phone's net capabilities, but you're not really supposed to be using them while driving anyway, so... I can read SMSs while they arrive (this in an A6 but it is the same as in A5), they get saved on the SIM and MMI displays a small letter signifying arrival of message - easy to read on the go.

If I need to send messages or use online functions while parked, I just switch off the SAP from the setup menu.

No going back to Bluetooth HF mode for me, no matter the small inconveniences. The quality and realiability of phone calls is great and reading SMSs from the MMI screen when they arrive (instead of parking somewhere to get the phone out of pocket and reading) is an excellent bonus."


BTW: There are some warnings that the Audi SIM Access Profile accessory (for Bluetooth Low) would not work with MMI 3G, but this is unconfirmed information, and I am not sure if Bluetooth Low is even shipped for MMI 3G.


rSAP or Remote Sim Access Profile..??

">Does anyone know if its easy to "upgrade" from Low pre to High with SAP phone prep?

It is.

Two possibilities... First the easier one that gets you SAP that is usable like a mobile phone connected with an adapter to your center console dock would be, so very useful if you have Bluetooth audio issues. You could get this:

Adapter mit SIM-Kartenzugang
Artikelnummer: 8P0051440


That is an official Audi accessory and just plugs into your existing phone dock in the center console. It works for both cars without navigation/MMI and cars with navigation/MMI. It basically adds a phone in the car dock that uses SAP to get SIM data from your phone, very easy and good accessory I hear.


Now, if you want to go for the full factory kit and your car has navigation/MMI (which you seem to have) and the phone-prep low, you need to change your telephony unit to a SAP enabled one. If you live in the Europe, your telephony/Bluetooth unit is already one with MOST fiber-optic cabling and you just swap the unit out (will need some pin changing in the connectors but that's about it) and VAG COM coding and that's it. In the U.S. on some Audis the telephony module is not MOST fiber-optic based so you would need to wire fiber-optic cabling there if that is the case.

If you have the MOST connected module already DO NOT just swap it to the new one, you will blow the new module up. You need to rewire some connections in the connector, see the thread linked below (and navplus.us forum's MMI area). Otherwise it is plug and play as everything else needed is already in the car (antenna, microphone etc.). The center console dock I believe becomes inoperative with the SAP module, it is not used.

Kufatec.de can sell you a used module cheaper, or your Audi spareparts desk can sell you a new one.

The module is under either of the front seats depending on market. In the U.S. I believe under front passenger (right), in Europe under driver (left side).

A useful to read about this:

MMI phone prep with SAP profile

A guy who retrofits these in the U.K. (craigyb):



Voice Control Question

"All MMI based Audis (well, considering pre-3rd gen anyway) that come with Bluetooth phone-prep include two modes of voice control (either will be enabled depending on market and car settings a maintenance shop or VAG COM user can adjust):

1) Phone voice control with dialogue. Language can be selected by maintenance shop or with VAG COM. Limited speech dialogue to control phone functions.

2) "Speaker dependent" voice control without dialogue. Very limited mode that is language independent in that it only recognizes user-programmed voice tags and answers with beeps.

Only exception is some U.S. Audis that have the phone speech control disabled, but it too can be enabled with VAG COM (it is just flipping a bit on). All (current anyways) MMI phone-prep cars come with both of the above in hardware, either (or neither in some cases, e.g. if the third option below is installed) is enabled via software configuration.

Third kind is available when the car is fitted with speech dialogue system:

3) Speech dialogue system with controls for phone, radio, CD, navigation, directory. Correct language module must be installed in car, only one language fits inside the module software at a time (upgrade CD can be used to install new language). This is a module inside the radio module in trunk, very easy to retrofit too.

For the VAG COM options to configure either of the two first options here:

Interesting VAG-COM codes for Audi A5 - probably A4 B8 too, maybe A6 etc. as well

For retrofit instructions (A5 with navi is same as A6) for full speech dialogue system see end of this article:

Bluetooth phone prep and speech dialogue system retrofit Audi A6 (4F/C6) Avant MMI High (possibly relevant also for Q7/A8)

"The speech button picture on the steeering wheel has nothing to do with MMI vs. AIS or phone voice vs. full speech dialogue. It is a model-year pre-2009 and 2009 difference, Audi changed the long-standin sound waves picture to the talking head one for some reason (maybe it is easier to understand?).

BTW: The full speech dialogue system is extremely useful in entering navigation addresses which can otherwise be a bit of a pain with the MMI wheel..."


Steering Wheel Question

"Well... some aftermarket solutions tap into the steering wheel controls, it might be possible to use one of them (I know Parrot products have been installed in Audis).

Such as this:


You could always retrofit Bluetooth to get phone and thus voice control for the phone. The instructions below are for MOST/full MMI cars (2G, not 3G), but many basics are similar for Concert/Symphony radio if you have that, so you get some feel to what is involved, only thing different is that with Concert/Symphony there are no optical cables to wire, just different kind of CAN/K-line wiring... contact Kufatec.de for a kit.

I have not heard of any solution (VAG COM or otherwise) to reprogram the speech button to do some other in-car function, though.

Bluetooth phone prep and speech dialogue system retrofit Audi A6 (4F/C6) Avant MMI High (possibly relevant also for Q7/A8)

Notes on alternative (easier) retrofitting of phone prep in glove compartment Audi A6 (4F/C6) https://a6retrofit.tripod.com/articles/a6gloveprep.html"


Useful links:

Getting Audi phone-prep/SAP phone to download Nokia smartphone contacts

Setting Up Bluetooth - iPhone with Audi


UPDATE 12.1./13.1./19.1.2010:

Notes and links about retrofitting MMI 3G Bluetooth in an A4/A5:

Bluetooth installation after delivery possible?

Phone prep low

Finnish reading audience may want to read these Finnish notes as well:

UltimateVW.com: Audi A5/S5 & A5 Sportback (sivut 146 - 147)


By LoCal

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