I am looking for some information on these modules My car has a BM54 Harman/Becker module XQC000140 and it appears to be broken as i have zero sound from the speakers. What im wanting to know is does the BMW BM 54 Becker Professional fit in its place? As I have been given one which is in full working order but still gives me zero sound. BMW part number 65.12-6 919 078 Many thanks Fraser

I have heard a romour that the becker fits the bmw professional cars but the professional models do not fit in the becker equiped car. Just looking to confirm.

From my small amount of research into the BM54 there are only 3 versions:

Very early, round plug types.
Middle square plug types (type we have)
and the newer square plugs same as above - we can use these and they give us extra features.

The fact that you get no sound points to the amp - rather than the BM54 RADIO module. 

The reason im looking at the BM54 module is because I have replaced the DSP amp with a brand new one from Land Rover. What else could be preventing sound coming from the speakers? I do hear sound very faintly from the front speakers-I do mean very very faintly but it definately ties in with whatever is being displayed on the tv or radio.

If we get to the bottom of this I would like the topic of the BM54 module and DSP to become a sticky as the cars age we will be seeing more and more issues like this.

Many thanks Fraser

No need for a sticky as thats what the Wiki is for. It could definitely be added to the common problems page! Feel free to add it...

Have you had water that area in the past? That tends to be the culprit - I know Dolphinboy has had similar problems - but he has narrowed it down to the amp specifically.

Maybe bug some members locally to you to see if they wouldn't mind let you try swapping known good units around? I would say I would help, but a, I live a million miles away and b, I have logic7 which is a different amp.

If I do the BM54 upgrade soon though and you're still having probs I will gladly send you my old BM54 to try out, but I'd have to see a new one for super-cheap.

D 

Thats a kind offer Dan-I will certainly accept it if im still having problems. I didnt have a dsp option on my screen-so replaced that and now I have the option but still no sound. So I have taken that out of the equation. In my eyes it can only be the BM54 module which I have tried a further two in (unfortunately they were the professional ones) so not sure if they are compatable.

If anyone in the area ( central scotland ) wishes to assist it would be greatly appreciated, I do all the travelling and work.

Many thanks Fraser

Actually, I have to disagree with Dan here. The sound systems are somewhat primitive (really! ) and the BM54 has a high level out - which goes to the speakers in some BMW's and the premium system's amp or the DSP amp in our RR's. All are high-level-in amplifiers. And the BM54 is known for being less than robust.

That said, not having the DSP option on the screen then suddenly having it does point to a bad amp. Do you have water in the electrics area in the boot? 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)

As soon as I purchased a new DSP the DSP option returned. Thus making me think the only other thing left to replace was the BM54 module. Yes I stripped the old DSP and BM54 and both showed signs of water ingress.

Every item on the i-Bus network sends out an identifier. When the head unit receives an identifier - eg dsp amp, FBH w/park heating, TV module - it adds that menu item. Your old amp was likely no longer telling the system 'hey, I'm here' because because it was dead (or simply comatose? ).

If you like, you can send me your BM54. I have a guy who can do repairs if the water damage is not too bad. PM me if your interested.

Make sure you find the source of water ingress before you kill your new components too. A diaper in the bottom of the electronics compartment acts as a good tell-tale and absorbs smaller amounts of water. 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)

Thanks again for the offer. I'll see how it goes. I'm still waiting on somebody being able to say either way if the BECKER PROFESSIONAL works in cars that originally had the HARMAN BECKER unit installed? Iv also checked rave, could somebody tell me the order of where the power goes and what sends signals where when the power comes on?

*** UPDATE***

Right I have fitted the new BM54 i recieved, its the proffessional model. I can now hear music and can identify it getting louder and quieter when I turn the volume up or down. But when it is turned up to its fullest its barely recognisable. This would suggest that the module is working but the sound isnt being amplified enough-any ideas guys? bearing in mind the DSP is brand new.


Fraser

I'm not sure what a Becker Professional is, but as I said our DSP has a high-level line-in (so the BM54 needs a high level line out - not a preamp out). You'll need to check with someone who knows BMW systems. I'll try my electronics guy tomorrow. Are there any other markings on the unit (PN's, etc)?

If the 'Professional' only has low-level out, you could just buy a small 4 channel amp for in-between...  
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)

Here is a link to a BMW BM54 Professional module.
http://cgi.ebay.co.uk/BM54-BMW-RADIO-12-MO...41560b7334
What do you mean by PNs?

It could well be the module isnt 100% compatable-I really dont know.

PN's = Part numbers? Ian

The BMW becker professional part numer is 65.12-6 919 078 and the old L322 harman becker part number is XQC000140

Fraser

I have had the same problems as you and have not yet found a solution - in fact, I have given up on this!

The problem is that in my case, the Radio is good, and probably the DSP - the low sound level comes from the fact that the DSP (apart from at initial start up) never receives an instruction to increase the volume. As far as I have seen with Navcoder, the display and the steering wheel controls send instructions to the radio (which gives a constant level output in DSP mode) to increase the volume, but the radio never communicates these on to the DSP.

My solution has been to hard wire directly to the speakers by making a jumper from the Radio out to the DSP out - this gives a good audio output, although not the same quality, or through all of the speakers, as you would get with the DSP.

As far as I have identified, the fault is either with the radio not forwarding the messages to the DSP, or with the IKE or onboard computer in sending the messages to increase volume to the wrong place.

After speaking with Joachim (Navcoder) it appears to be the former - but I have changed the radio, as you, to no effect!

To jumper the radio, you will need to reset it by removing its connector - it will then see that the DSP is not present and provide a variable level output rather than a fixed level.

As to the faint level that you hear, this is a mystery - I presume that this is cross talk in the Radio, as nowhere in monitering the iBUS do I see any instructions to the DSP (I saw this as well).

If you persevere, and find a solution, please let us know - I had two new radios + the original, and two new DSP's, all from landrover, and did not find a solution!

Hi Steven,
I was wondering what ever became of your radio problem. I was going to give you a shout the other day but I've misplaced your mail address.

So, the system is not as primitive as I thought with high level out on the BM54 and high-in on the DSP - I should've known. The i-bus identifier from the DSP amp puts the BM54 in low-level mode then? I'll look at the wiring diagrams when I get a chance, but I find it hard to imagine that it has anything to do with the IKE as this is the gateway between the i-bus and the K- and CAN-bus and the amp and radio all sit behind the IKE within the 'i-bus-area' on the infotainment harness. AFAIK, the only thing the radio/amp have to do with anything outside the i-bus network is the speed signal. Then again, I'm not going to argue with Jochen
( ). Do you have a Resler interface? It should actually be relatively simple to hook the interface to the i-bus wire at the DSP connector and check the logs for the volume signal. Maybe you will have to make the trip to the Alsace for some beer and RR playing .

Sorry for the hi-jack, Karmann. So it won't be the sensitive amplifier in the BM54 - you're still going to need another BM54 to try. IMO, that will be the easiest way forward for you as you'll be eliminating the 'easy' faults. An alternative is to do as Steven did and cut the DSP out of the loop.

cheers
Steve 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)