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Hi, I'v got a 147 with the Bose audio system and I want to upgrade my head unit for better interface with my Ipod. I'm pretty clueless with what leads I need to connect the HU to the Bose Amp.

the head unit is JVC KD-PDR51.

Any ideas? Thanks!
 

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AO Silver Member, 155 Lounge Winner 09
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main connections are:
1. powerwiring: alfa plug = ISO style
2. speakerwiring: alfa plug = ISO style
3. remote trigger wire: triggers Bose amp on/off when you turn the headunit on/off; alfa plug = YELLOW mini-ISO plug
4. antenna connection; alfa plug = ISO style

steering wheel controls are not applicable with this headunit (from reading the specs on website).

i believe the headunit comes with a wiring harness that has ISO plugs on the end. this makes for plug-and-play to a large degree.

the alfa power/speakerwire ISO plugs should look like this (from google search): http://www.elisenet.plus.com/images/TweeterPods/ConnectorLug.jpg

so, the powerwiring is simply an ISO connection. however, you must alter the wiring to suit the alfa. the main +12V powerwire is in position #7 in the alfa plug; this provides 'constant' +12V (ie: always live), and provides power to run the unit and memory back (eg: radio presets). this wire must connect to the YELLOW powerwire going to the jvc. (other cars usually have this wire in position #4)

if your car has a wire at position #4, it will be a 'switched'/IGNition +12V wire (ie: 0V with ignition key at OFF, +12V with key at ON/MAR). this wire needs to connect to the RED powerwire going to the jvc. it triggers the headunit on/off when you turn the car on. if this wire does not exist, you can tap into an alternative switched wire. usually the cigarette lighter powerwire is suitable.

speakerwire ISO plug is a direct connection, without altering the wiring pattern. this provides the audio signal to the Bose amp. however, the jvc will provide an amplified (ie: high level) audio signal; so each increment of the volume control will bring a relatively big increase in sound. this compares with the factory headunit which provides a 'low level' audio signal via its speakerwire outputs; it is a feature of the Bose-compatible headunit.

the jvc can provide a low level output, but via the RCA preout terminals. you will need an adaptor to convert the 'phono' style terminals to a speakerwire ISO plug. if the volume control ends up too crude, you may need to investigate this further; see below.

to trigger the Bose amp on/off you need to connect the jvc's remote output wire (should be BLUE/WHITE) to the wire in the YELLOW mini-ISO plug (refer to schematic stuck atop factory headunit; wire is labelled 'BOOSTER').

nexxia offer an adaptor harness (PC-2-36-AMPR), and probably a good way to go: Head Unit ISO Connectors

the antenna plug on the jvc is probably a DIN style plug, typical of japanese models. if the jvc does not include an adaptor plug, you will need one.

http://www.siocommunications.co.uk/Autoleads_files/DIN-ISO-pic.jpg

the above probably all reads as 'complex', but it's not really. it's mostly plug-and-play. you just have to understand where you need to make minor alterations (powerwiring), and the implications of the audio signal.

:)
 

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Hi, Ive just installed a JVC KD-BT11 in my GT (with Bose audio), thanks in no small part to the info in this thread - thanks to shiny_car! All seems to be working perfectly now, cept one thing - I cant turn the head unit on at all without the ignition on. Is this normal/to be expected?

When I had the unit installed first, it was wired incorrectly - I had an always on 12V connected to the switched (RED) input on the head unit. Then, I could turn in it on with the key out, but it didnt turn on/off when i turned the key. Any thoughts - is there a happy medium?? :)

One other question - would anyone have any info about connection a jvc unit such as mine to the remote steering wheel controls? I believe this is possible, i found some into about it on the net when i was browsing and deciding what unit to buy, but now i cant find it again!! Thanks !!
 

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I cant turn the head unit on at all without the ignition on. Is this normal/to be expected?

When I had the unit installed first, it was wired incorrectly - I had an always on 12V connected to the switched (RED) input on the head unit. Then, I could turn in it on with the key out, but it didnt turn on/off when i turned the key. Any thoughts - is there a happy medium?? :)
unfortunately, no easy happy medium. unlike, say, a Japanese car, there is no ACCessories ignition key position - only OFF/ON.

however, what i have done in my car is add a manual toggle switch, which i've mounted under the dash (out of sight, but within easy reach). the (RED) ACCessories wire on my headunit connects to a 'constant' powerwire; for example, it can be shared with the (YELLOW) main wire that goes to the alfa #7 wire. but, add the toggle switch along the red wire (will need to extend the wire so you can mount the switch where you wish).

so this makes the headunit independent of the ignition key. and you can manually switch it on/off via the toggle switch.

'how does this differ to wiring the (RED) ACC wire straight to wire #7 without a switch?', you ask? cos you can still manually turn the headunit on/off via its power switch. with the jvc, there may be no difference. however, with an alpine headunit like i have, the headunit does not power-down completely unless the ACC wire is killed. so if i didn't have the toggle switch - and even by detaching the face or turning the headunit off manually - it would remain in stand-by, but not fully off.......and the battery can be drained after a week if not driven.

so, that may be a happy medium for you: rewiring the RED wire to #7, shared with the YELLOW, and adding a manual switch.

One other question - would anyone have any info about connection a jvc unit such as mine to the remote steering wheel controls? I believe this is possible, i found some into about it on the net when i was browsing and deciding what unit to buy, but now i cant find it again!! Thanks !!
the UK-spec model must differ to the Aus-spec ones, cos the Aus jvc website makes no reference to steering wheel control inputs, and the downloadable manual does not feature it.

the UK jvc website does indeed specify your model as being Steering Wheel Remote Ready. if this is the case, there should be a 3.5mm socket (or similar) at the back of the headunit, to connect an interface (it is NOT the same socket as the 'external components' one).

if the socket exists, then it looks like nexxia offer a suitable interface (2-piece, with a harness (CTSAR001), plus the actual alfa-jvc adaptor (CTJVCLEAD)):
Alfa Car Radio fitting kits

so you need to confirm the socket exists at the back of the headunit. then maybe contact nexxia to confirm compatibility. there of course may be alternative brands for an interface.

:)
 

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speakerwire ISO plug is a direct connection, without altering the wiring pattern. this provides the audio signal to the Bose amp. however, the jvc will provide an amplified (ie: high level) audio signal; so each increment of the volume control will bring a relatively big increase in sound. this compares with the factory headunit which provides a 'low level' audio signal via its speakerwire outputs; it is a feature of the Bose-compatible headunit.

the jvc can provide a low level output, but via the RCA preout terminals. you will need an adaptor to convert the 'phono' style terminals to a speakerwire ISO plug. if the volume control ends up too crude, you may need to investigate this further; see below.
Hi, resurrecting this thread once again! As mentioned in my previous post, I fitted my JVC headunit a while back. However, I just connected directly used the ISO speaker connections and as mentioned the volume control is a bit coarse as a result - also, you can't turn the radio to a low volume - its either quite loud or off. So, I'd like to rewire it such that I'm connecting a line level output to the amp. You mentioned I can do this using the RCA outputs, but would need an adaptor. However, I can't figure out which is the correct one in the nexxia.co.uk link provided. Could you point me in the right direction?

Also, the ISO connections currently have four outputs for the four speakers - i.e. front left, FR, RL, and RR. However, the RCA connections are (I presume) 2 channel. Does this mean I'm going to lose sound in my rear speakers, or will the adaptor deal with this?

Thanks for the help!

Adrian
 

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if the jvc only has 2 channel preouts (1 set of preouts), then you can either:
1. run only the fronts (and sub which i presume takes its signal from the front (possibly not though))
2. 'splits' the preout into 4 channels using RCA Y-splitters first

Y-splitters: you will need 2x 1M-2F versions (male/female terminals)
*nexxia PC1-1M
*look like this: http://www.autoaudio.com.au/images/22CM-1-MALE--2-FEMALE-RCA-Y.jpg

the nexxia adaptor is the PC2-36-AMPR (mentioned in first reply)
Alfa Car Radio fitting kits
http://www.nexxia.co.uk/Car_Stereo_fitting_kits/images/PC2-36-AMPR.jpg

:)
 

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Have a JVC KD-BT11 in mine :cool: Bluetooth ideal and I managed to buy it on clearance from Argos via E-bay for £50. I cannot find any reference to connecting to an external stering wheel controls although you can buy a remote. I have mine on the perminent +ve anmd turn it on and off. Note there is an attenuation function via the on off button to reduce the level rather than just switch off and it mutes the cd/radio on bluetooth calls anyway.
 

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yeah, i don't think the KD-BT11 has a steering wheel interface input socket.

:)
 

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newbie on here after info on the bose connections

Hi people firstly want to congratulate you all on a fantastic forum :thumbs:

I am looking at buying a 156 derv probably going to be the 1.9jtdm after hours of reading on here. I'd ideally like to get one with the Bose system in it and just want to confirm that what I have read is right. The factory fit head unit outputs the audio through the ordinary 8 pin ISO as the the none amplified system does but the audio is at low level and only the amp trigger is fed from the yellow mini ISO. The reason I am asking is that I have a Blaupunkt Nashville 35 DAB head unit which has all the low level outputs on the yellow mini ISO. So all I would need to do is make an adaptor cable taking the standard ISO to the mini ISO.

Thanks for your help
 

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correct.

the only potential issue is that the low level outputs from your new headunit provide a signal voltage that is lower than the factory model. and as such, the volume from the stereo may not be loud enough (or it will be significantly softer than the factory setup). but hopefully it's still 'loud enough'; ideally the low level outputs are rated as '4V' preouts. '2V' can be adequate, but less than this and it may end up too soft.

:)
 

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thanks Shinny i'll have a read of the instruction manual (that will be a first, but I knew if I kept it long enough it would come in for something!!)
 

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