We have found that OTHER Bluetooth vendors use OLD first generation Bluetooth control modules, they also have cheaply made homemade connectors that can be easily miss-wired or fall out while driving. These other vendor solutions are detailed below with pictures directly from their users guides.
Whatever you do do NOT get the 84 21 6 934 552 end of life 06/03 1st generation ULF module anywhere. This module has poor Bluetooth performance and poor audio quality. Also I would highly recommend you to stay away from other vendors who claim to "modify" the ULF modules to increase the audio volume. I have heard from quite a few people who had another Vendor's Bluetooth kit that "crapped out for no good reason". We have a number of these other Vendor ULF modules that were modified to boost the audio, and it seems that they are burning up internally from certain modifications that force the unit to operate outside their original specification. If you would like to see a burned up "modified" 552 ULF module from other vendors, we would be happy to show them to you as they are becoming more and more common these days.
We DO NOT offer modified ULF modules, but only have the latest generation, highest performance ULF modules that we can find worldwide. These ULF modules are more expensive than the older first generation ULF modules and we do not pass this extra expense on to our customers.
Other Vendor Bluetooth Kit Wiring Adapters:
The following instructions are directly from ANOTHER BMW Bluetooth retrofit vendor's installation instructions the the E46. As you can see THEIR cheaply made, homemade harness below can easily be miss-aligned or fall out while driving. --- Bimmernav.com uses original BMW connectors in our Bluetooth harnesses, with the wiring preconfigured to properly fit your exact model and build date of your vehicle. No concern on lining up pins incorrectly to miss-wire and blow a fuse with the Bimmernav solution.
The following instructions are directly from ANOTHER BMW Bluetooth retrofit vendor's installation instructions the the E38/E39. Their cheaply made, homemade harness as shown connected directly to the ULF module (see colored wires just flying out of the left side of ULF module) can easily be miss-aligned or fall out while driving. --- Bimmernav.com uses original BMW connectors in our Bluetooth harness, with the wiring preconfigured to properly fit your exact model and build date.
The following instructions are directly from ANOTHER BMW Bluetooth retrofit vendor's installation instructions the the E38/E39. Their cheaply made, homemade harness is shown connected directly to the DB25 connector has loose wires that you need to connect to the cellular phone booster (see extra wire) which can easily be miss-aligned or fall out while driving. Not only does this extra wire have the ability to fall out, you will no longer be able to use the BMW cellphone booster with your phone's snap in adapter! ---Bimmernav.com uses original BMW connectors in our Bluetooth harness, with the wiring preconfigured to properly fit your exact model and build. Plus our design is BMW original design and does not require you to loose functionality such as antenna boosting (BMW compensator)
Other Non-OEM Parts
Be careful when considering OTHER NON-BMW Bluetooth systems that operate on the vehicle I-bus. Other Bluetooth products that claim to operate via the BMW steering wheel buttons or other Radio controls using NON-BMW parts require you to install "foreign" parts into your BMW's communication bus system. These foreign parts are homemade electronic projects that did not undergo rigorous compatibility testing by BMW engineers. When these NON-BMW systems are installed in your BMW they are connected to the BMW I-bus digital communication system and operate by constantly monitoring and sending out their own manipulated BMW I-Bus messages to other modules within the BMW bus system in order to "trick" the other BMW components into thinking a message came from a BMW part. The challenging part in designing a NON-BMW part that operates on the Bus system is that BMW's I-bus messages are very specific and have requirements for exact voltage, and message formats. Any misinterpretation of those messages could be detrimental to the operation of ANY other components on the BMW bus system (see image).
BMW's I-bus messages are non-published outside BMW and NON-BMW developers create the data, operation and messages based on trial and error. Unfortunately not all of the I-bus messages are consistent with each model and year BMW. Any miss-calculation or miss-interpretation of the I-bus messages could cause damage, or faults in other non-related components. What may work perfectly in a test vehicle may be detrimental in your specific vehicle.
Component failure or interference on the I-bus system are described in the BMW troubleshooting documentation on the I-bus system which details the potential cause other faults in ANY OTHER device within the bus system of your BMW. To quote a few paragraphs in the BMW Bus System troubleshooting Documentation "A Faulted module may paralyze or take down the entire bus. This scenario would be evident by functions not being carried out and possible faults stored." AND "Excessive interference created by a defective alternator or aftermarket devices such as (Non-BMW) cellphones or amplifiers may induce a voltage into the bus line and disrupt communications. This type of interruption may be intermittent and faults may only be stored in some modules and not in others. These faults are often difficult to reproduce."
In addition, I have heard from customers who's dealers were denying warranty work, or blaming aftermarket electronics that are connected to the I-bus for failures of other components on the entire electrical system. They even have stated that this type of equipment could void the entire vehicle warranty.
Be smart choose Original BMW Parts for retrofitting your BMW. Get the most recent version BMW Original parts available, and do not mess around with aftermarket parts that connect to the BMW instrument cluster's communication Bus.
Bimmernav.com uses BMW Original parts in our BMW Bluetooth kits that have been tested for compatibility by BMW Engineering in the following vehicles (see link for details). Bimmernav uses the latest modules available from BMW that incorporate all of BMWs software and hardware revisions over the last 3 years! We insist on getting the latest BMW original components even if they are more expensive and harder to get as we know the latest components are the best available and perform at the highest levels, with the least amount of issues.