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The Bose Amp

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10K views 30 replies 11 participants last post by  JamesG86  
#1 ·
Afternoon all,

Was looking forward to installing my new Kenwood head unit this morning, only took me four hours and a few scrapped knuckles with all the GPS, DAB, Microphone etc...

Powered it up, all good but no sound. Then realised I'd not connected the RCA cables, still no sound. Sadly researched it and it appears my Bose amp is one of the later ones which requires the Can Bus to turn it on, not just the little blue wire :?

There doesn't appear to be loads of fix's or options for this, I definitely need the new unit. Does anyone know of a fix or if it's possible to change the Bose amp for something that will work?

Thanks in advance,

Russ
 
#3 ·
It is possible to generate the required CAN signals using say an Arduino and a CAN shield, but if you've never done any programming before it might be a bridge too far. Have you contacted Connects 2? As they make units that interface between the steering wheel CAN system and the analogue controls on third party head units, they may have made a unit that also generates the CAN signals for the Bose. Failing that, then your best option might be to get hold of an earlier Bose amp. The Bose amp uses low impedance speakers so if you go for a different amp then you would probaby need to change the speakers as well.

Another long shot would be to swap the head unt for an Xtrons one. I believe these can generate the required CAN signals but you have to set it to different vehicle so the steering wheel controls don't work (unless they've fixed it for the Latest models).
 
#4 ·
I've never heard of that problem before I thought all Bose amps were all the same
Don't know for sure but:

According to the wiring diagram, the Bose (J525 - Digital Sound Control Module) is connected to the infotainment bus. There have been several posts from people who couldn't get sound after installing an Xtrons with a Bose but cured it by setting the CAN settings to a different car. This is consistent with what the OP is saying.
 
#8 ·
John949 said:
Another long shot would be to swap the head unt for an Xtrons one. I believe these can generate the required CAN signals but you have to set it to different vehicle so the steering wheel controls don't work (unless they've fixed it for the Latest models).
Latest models are all plug & play. You don't need anything extra at all. However I believe that unless you get an Xtrons from Ebay or Amazon, you might have to wait as there aren't any units on the main Xtrons site. Possible that they're bringing out a new HU soon.
 
#9 ·
I emailed a company last night who repair and exchange the TT bose amp, they said that the Can Bus DOES NOT control the amp turn on, it's only used for diagnostics;

"Hi Russell

None of the Bose units are controlled by canbus .. this is only for diagnostics ... the issue will be the remote trigger ' on ' wire .... if you go to our support page .. password is library - there is a wiring diagram for the amp ... check you have a 12v trigger to pin 29."

I guess these guys are the Bose experts? Will look into this pin 29 more and see how I get on.
 
#10 ·
The bose amp will need recoding from a digital to analogue signal to turn it on, I know this becase I've done it on a fellow members car who fiited a Pioneer HU to his Bose system. As soon as I made the change, with VAGCOM, it powered up straight away.

You might also need to change a wire too, I didn't do that bit for him.
 
#12 ·
UPDATE - FIXED!!!!

I had the mobile technician visit today, he's not come across this problem before but re-programmed the Can Bus settings to the Bose amp and it now switches on! Best ÂŁ60 I've spent (well nearly...) I think. So pleased this was all I needed to do.

Just need to dry the carpet out now and hopefully that will be me up and running!
 
#13 ·
Audi Russ said:
UPDATE - FIXED!!!!

I had the mobile technician visit today, he's not come across this problem before but re-programmed the Can Bus settings to the Bose amp and it now switches on! Best ÂŁ60 I've spent (well nearly...) I think. So pleased this was all I needed to do.

Just need to dry the carpet out now and hopefully that will be me up and running!
https://www.totalcardiagnostics.com/sho ... stech-vcds

ÂŁ56 including postage...
 
#14 ·
I know my Xtrons uses the CAN Bus to switch on and off because it won't power up on the bench without the CAN bus signal. Also if you turn the key fully off but leave it in the ignition, the unit stays powered; so it is using the 'Key out' signal (2C3 10) on the CAN Bus to turn off, as opposed to the 'Ign off' signal (2C3 11) Does the CAN switched Bose behave the same? Is this a way to tell them apart? Note that I'm talking about the amp not the head unit. My old BNS switches off with the IGN off, don't know what RNS or Chorus do.
 
#15 ·
Audi Russ said:
UPDATE - FIXED!!!!

I had the mobile technician visit today, he's not come across this problem before but re-programmed the Can Bus settings to the Bose amp and it now switches on! Best ÂŁ60 I've spent (well nearly...) I think. So pleased this was all I needed to do.

Just need to dry the carpet out now and hopefully that will be me up and running!
Told ya :p

Next time, if you need something doing, post up your location as there may be someone local with VAGCOM that will do it free for you.
 
#17 ·
Audi Russ said:
UPDATE - FIXED!!!!

I had the mobile technician visit today, he's not come across this problem before but re-programmed the Can Bus settings to the Bose amp and it now switches on! Best ÂŁ60 I've spent (well nearly...) I think. So pleased this was all I needed to do.
Hi there,

I have also just installed a Kenwood head unit, had it done by an audio place. Also have Bose system. Do you experience any difference in sound quality? Have been reading that there can be problems if you just change the HU and still have the Bose amp and speakers? My sounds is now much worse, from all sources ... Have changed lots of diff EQ settings/profiles in Kenwood unit and sound still worse than before ... Saw that you also had Bose system so would be interested to hear what you think. My Kenwood model is DPX-5100BT.
 
#18 ·
barry_m2 said:
Audi Russ said:
UPDATE - FIXED!!!!

I had the mobile technician visit today, he's not come across this problem before but re-programmed the Can Bus settings to the Bose amp and it now switches on! Best ÂŁ60 I've spent (well nearly...) I think. So pleased this was all I needed to do.

Just need to dry the carpet out now and hopefully that will be me up and running!
Told ya :p

Next time, if you need something doing, post up your location as there may be someone local with VAGCOM that will do it free for you.
Do you guys know what the actual coding changes are ? [smiley=book2.gif]
 
#19 ·
Hi Polymoog,

Yes I just saw your earlier post. I actually went for a long run today and was thinking how good it sounded for an old car (sorry this doesn't help you at the moment...). I was going to go for an Alpine unit as I rate them highly but the cheapest one I could find was ÂŁ500 so went with the Kenwood around ÂŁ350. Mine is the DMX717 I think.

Apart from the amp not turning on at first it all went fairly smoothly with no problems. I would guess that there's a problem somewhere else rather than the head unit? It should improve the sound if anything. Have you tried another wiring harness? The RCA cables all look good and connected well?

I think the technician said he'd change canbus code to send an analogue signal to the amp to turn it on rather than a digital one?
 
#20 · (Edited by Moderator)
I am assuming 0xxx?xx was changed

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#31 ·
I am assuming 0xxx?xx was changed

View attachment 431619
Thanks everyone here for providing this information, with an ODB11 Pro kit I was able to do this myself. It is indeed the activation area on this coding, mine was set to 3 (1 + 2), meaning remote wire and signal level to turn on amp. I set it to 1 and the amp switched on via my Kenwood head unit from just the blue wire.
 
#23 ·
Hi Russ,

Thanks for your reply!

OK interesting. I think my model is probably a bit more of a budget option, cost 1500 SEK which is around ÂŁ120. Had it installed by an car audio place so do not know how they wired it. However I could ask them re what signal they had set to be sent to amp, thanks for the tip.

Played around a bit more this eve and changed speaker sizes in the Kenwood settings which helped a bit, but sounds still sounds "canned" and bass not brilliant. Did however get tweeters to give a more balanced sound.

Are your speakers original? Was thinking that after 13 years, mine might be a bit worse for wear, don't really know the life expectancy of speakers TBH?

Katrina
 
#24 ·
Hi,

The only reason you'd need to ask about the signal to the amp is to switch it on, if your amp is on (which it obviously is) I don't think there's anything they can do with VagCom?

If it sounded fine before you changed the unit then your speakers must be fine. I'd take it back to the installers and perhaps ask then to try another head unit first? If no different then then the wiring they used?

I'm wondering, is there a setting on the head unit with regards to the volume/signal coming out of the RCA's?
 
#25 ·
#26 ·
Audi Russ said:
Hi,

The only reason you'd need to ask about the signal to the amp is to switch it on, if your amp is on (which it obviously is) I don't think there's anything they can do with VagCom?

If it sounded fine before you changed the unit then your speakers must be fine. I'd take it back to the installers and perhaps ask then to try another head unit first? If no different then then the wiring they used?

I'm wondering, is there a setting on the head unit with regards to the volume/signal coming out of the RCA's?
Sorry missread you first reply re amp signal ....

Sound was not fantastic with original HU but did not expect it to be worse after installing the Kenwood. Obviously some limitations due to sound source, MP3 not going to sound like original CD, but even CD's do not sound quite the same as before ... However just seems like the speakers in the Seat handle crappy MP3 much better than mine, perhaps because they are newer.

Will check settings again re signal coming from RCA's. [smiley=book2.gif] Thanks for your help!