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AUX Input for OEM Acura/Bose Radio

RYU

RYU

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I've been using the GROM iPod adapter for a couple of years now. It's been trouble free but i've outgrown my iPod. These days i've been on my Android streaming music through it while also using Turn-by-turn Navigation. In my other cars I ran an "audio aux" 1/8" audio cable directly to my crossover and it works great. I really want to do this on the NSX but the NSX is the only car I own with the archaic OE system still in it.

Here are the options I've found to create an AUX input. Hope to get some feedback from you folks. (p.s. if there's already a thread on this kind of info please advise. I found none in a search)

alpine-wiring.gif


1. I know I can hack into the CD changer cable and pick up my left/right pre-amp signals inputs thru there. I should be able to quickly patch through a 1/8" plug to rca adapter of some sort so my Android phone can stream into it. The problem I have is I don't know how to trick the OEM headunit to think the CD changer is still there. I believe the BUS (Pin#1) needs some trigger voltage for this. I have no idea what voltage that is... Anyone know?

2. The other option is to keep the factory CD changer in place but cut/splice into the left/right audio inputs (i.e. Pin #5,4,2). This will keep the head unit thinking the CD changer is still plugged in but the Android device will intercept the audio signal. I hate this option because it's just ghetto since I have a useless CD changer still in the car but it works.

3. Call it a day and just buy this...Who's used this before?
http://www.installer.com/item/display_item.php?it=hon-aux
 
My USA spec has both ipod and rca inputs. I play my Sirius radio using the headphone jack with a headphone to RCA adapter. No fm hiss or interference. Also tried it with my Blackberry and it worked great.
Peter
 
Peter, thanks for reminding me! I believe you're right!

USB Connection: GROM-USB car stereo adapter connects your USB 2.0 device such as flash drive, external hard drive or mass storage device to the stock stereo in your car. With GROM-USB you can listen to your digital music library and control the playback through your car stereo controls.

iPod/iPhone Integration: Connect your iPod/iPhone to the car stereo. Control music files with the car stereo or steering wheel controls, browse by folders and files, and charge your iPod/iPhone.

AUX Input: 3.5 aux connection for any additional audio source (such as DVD, MP3 player, XM and more).
Click to expand...
 
Yeah, I think both USA-Spec and Grom have new units that offers Aux In. Check with them.
 
Apparently it's not a simple on/off trigger on the M-bus. It's an actual protocol required for the headunit to communicate with the CD Changer. Since I understand only about 50% of this mess I'm left with my #2 or #3 option. If I was an EE this may have been fun.

btw... i've decided i'm not going to use my Grom ipod adapter for this so i've already put in an order for #3.

Here's the protocol for the brave...originally found here
Alpine Car Stereo CD Shuttle/Changer Protocol
Protocol Description:

This is called either Alpine AI-Net or Alpine MBUS.
This document describes the protocol that an Alpine Car Stereo head unit uses to communicate with a 6 disc CD shuttle.

Information Sources:

1) Samples were measured and responses examined from an
"Alpine 7513 Digital FM/AM Cassette" head unit, from a 1995 306XSI Peugeot

2) The 0x994ghijklmnopqr packets were partially decoded from:
http://www.cus.org.uk/~cleggy/discus/messages/2/71.html

3) The author's email is: hone_heke at hotmail.com
Physical Connections:

Head-unit DIN connector:
Standard DIN 8-pin male plug (fits Dick Smith Electronics part P1571)
Has a data wire, stereo line input, battery and accessory line connections.
Pins are labeled in the manual (see 7513din.gif) and also on the circuit board.
Also see 7513controls.gif for the button layouts.
Link Protocol:

The Data Bus pin uses the Alpine AI-Net or MBUS protocol.
It is a common bus using TTL signal levels:
5v = logic 0
0v = logic 1
The head-unit maintains a logic 0 with a 22kohm pull-up resistor. (source: lost url?)

Serial data is transmitted at 1200 baud.
Each data bit (x) is sent with a 4 bit encoded sequence:
0 x 1 1
Packets are constructed with a series of 4 bit nibbles.
Each packet is followed with a checksum nibble.
It is calculated with the XOR of each nibble, then add one.
The sequence is begun with a packet sent from the head unit followed by at least one reply packet from the the cd shuttle.
The head unit will send a packet at varying rates down to about one every (two?) second.
Packet Descriptions:

Each packet begins with a one nibble device identifier:
0x1 = head unit
0x9 = cd shuttle
Followed by a command of one or two nibbles
eg. from the head unit:
0x8 = are you there?
0x11 = playback control
0x13 = track selection
0x14 = playlist mode
eg. from the cd shuttle:
0xF = error signals
0x94 = shuttle status & track time
0xB4 = shuttle status
Packets:

Head unit to cd shuttle:

0x18 = are you there?
This is sent every two seconds until a CD shuttle is detected.

0x111gh = playback control
g bit 3 = if set then power up cd shuttle (if not already)
g bit 2 = if set then power down cd shuttle
g bit 0 = if set the resume playing
h bit 3 = if set then play at fast forward speed
h bit 2 = if set then play at rewind speed
h bit 1 = if set then play is paused
h bit 0 = if set then play at normal speed
power up requests can be sent without requiring a change in the play speed.

0x113ghij0 = sent when a new track selection has been made
g = BCD (binary coded decimal) for the selected disc
hi = BCD for the selected track
j bit 1 = if set then play is paused
j bit 0 = if set then play at normal speed

0x114gh000 = sent when a new play list mode is set
g bit 3 = if set then REPEAT ALL mode is set (also requires a bit 2)
g bit 2 = if set then REPEAT mode is set
h bit 1 = if set then MIX mode is set

CD shuttle to head unit:

0x9Fgh000 = error signals
gh = 0x00 for normal condition
0x30 for high temperature error state ( ---H is displayed)
0x01 for disc change malfunction ( E-01 is displayed)
0x02 for disc in player mechanism ( E-02 is displayed)
g = 1,2,4-15 then the line input is muted

0x994ghijklmnopqr = shuttle status & track time
gh = BCD for the playing track number
i = 0
j bit 0 = 1 for positive track time, 0 for negative track time
klmn = BCD for the track playing time in seconds
o bit 3 = if set then REPEAT ALL mode is set (also requires o bit 2)
o bit 2 = if set then REPEAT mode is set
p bit 1 = if set then MIX mode is set
q bit 1 = signal an error (causes head unit to select paused mode)
r = 0-3 for amplifier on, 4-15 for amplifier muted

0x9B4ghijopqr = shuttle status
g = BCD for the playing disc
hi = BCD for the playing track
j bit 0 = loading (disc number flashes)
j bit 1 = no disc (---- is displayed)
j bit 2 = no track (T--- is displayed)
opqr = same coding as opqr in the 0x994ghijklmnopqr packet
Click to expand...
 
I'm kinda in the same situation or at least the same ball park that this thread was started for. Here's what's going on. I have a 91 with OEM head. I removed the OEM 6 disk CD changer and plugged in an older model Grom ipod adapter (it has no RCA audio inputs). This worked great till I got an iphone and plugged it in. I wanted to use the iphone to play my music instead of the ipod (gadget consolidation) so I plugged the iphone into the Grom and got no sound but I could still control advance/rewind the songs. I tried plugging my ipod in and the same thing happened. I got control but no audio. I talked to a car audio shop on the phone and they said the older Groms may not be compatible with the iphone and that I may have blown something in the Grom.

So, what I really want to do is just have a simple audio input play into my system from my iphone headphone jack. That's it. Any of you wizards think I may be able to use my existing Grom by just splicing/soldering into the circuitry or in other words just bypassing the control fuctionality of the iphone input? I know USA Spec and the new Grom have the RCA inputs as well as the unit linked to in the first entry above but I'd like to just use what I have if it will work. Thanks in advance for any and all input.
 
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Why don't you just plug the phone directly into the Bose amps? Because you want to use am/fm radio? You can always use a switcher to switch inputs if you really want to keep the radio functional. Or just update the GROM. I don't quite get what the problem is.
 
@ TURBO2GO, I didn't know I could plug the phone into the Bose amps. Do you mean I need to find the input wiring to the Bose amp(s) and just splice into them with a mini stereo aux jack from the phone and that's it? If that is true then that is exactly the simple solution I am looking for. I gain nothing by being able to control my music from my OEM head if my iphone is mounted right next to it.
 
Kenny Thompson said:
@ TURBO2GO, I didn't know I could plug the phone into the Bose amps. Do you mean I need to find the input wiring to the Bose amp(s) and just splice into them with a mini stereo aux jack from the phone and that's it? If that is true then that is exactly the simple solution I am looking for. I gain nothing by being able to control my music from my OEM head if my iphone is mounted right next to it.
Click to expand...

Yes, you can go directly into the amp. Audax has done it and it works great he says. Post #14 here

Another member said that the volume level with the phone is a little low, but that can be easily remedied even if that is the case.

I am still not sure what the input jack for the bose amp is but I believe it is RCA, and you just need an 1/8" stereo to RCA wire.

i1.jpg


And I think everyone should read THIS thread.
 
TURBO2GO, great! So, where is the amp? I have plenty of those 1/8 mini jack to RCA cables so I am all over this. I just need to know where to plug it in. Thanks for the info.
 
I looked in my maintenance manual to try and find out where the amp is but there is nothing in any of the pictures that identifies any of the components as an amp. Is the amp part of another component?
 
Guys where is the amp? I don't know. Behind the radio? Can someone chime in here?
 
There is a individual amp for each speaker.

You'd have to rig the harness to tap into that output.

There's a lot of talk about tapping directly into the AMP. It is not an "easy job". Probably the same amount of effort that I needed to tap into the CD Change MBUS.
 
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Also that bring up 12v questions as well.... you rig the harness to tap into it... you remove the Tape Deck.

How do you trigger the bose amps? I'm sure there are MANY solutions... but you'll have to fuss with that as well.
 
OK easy enough. So Kenny here is what you need to do:

1) Buy this:

afterhead-factoryamp.jpg


Made by Science of speed. Sold here.

$30.

2) Unplug the harness from the back of the factory radio, plug this harness you just bought in.

3) You get your RCA input to plug the phone output into, and your 12V input to turn on the Bose amplifiers. You can just wire the 12V trigger to the switched (ignition) +12V on the same harness. You just tie the two wires on the SOS harness together (probably the blue and the red). If you want to only turn on the amps when the phone is plugged in, just insert a simple on/off switch in line. On and your amps and speakers are active, off and they are off.

4) The wire you need from the phone to the harness (behind the radio) is this:

21oYZChl39L._SL500_AA300_.jpg


$5 at amazon here.

If you want the Bose amps to turn on when you play music on your phone automatically without a manual switch and you want them off otherwise, you have to invest in one more $30 device:

31zmQXeF3zL._SL500_AA300_.jpg


Sold Here

This plugs in between the wire coming from your phone, and the SOS harness's RCA wire (one of them), and the 12V output from this device that turns on the Bose amps (when it senses signal from your phone) hooks up to the amplifier 12V "trigger" on the SOS harness. The blue wire.

OK? Do you have any questions? This is easy. Don't let it intimidate you, I can walk you through it.
 
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Looks good to me.

There are 4 channels on that harness. Likely L, R, Sub, Center (Between the seats)?

If the above is true.

Center you can forget about... you'll have to combine L and R and run it to the Sub.
 
I am following this thread as much as I can, but let me ask a few simpleton questions:

If the phone is hooked to the radio without the 12V option, then wouldn't the Bose amps turn on when you turn the radio?

Not sure why one would bypass the radio on/off switch unless the "options" available through the aftermarket head unit is nullified when the radio is on? I thought if you create 6 files of music categories, the radio presets get you to those files no? Or was that an option only with a Grom or USA Spec ....... now you know why i am so confused!!!
 
PoKnow said:
Looks good to me.

There are 4 channels on that harness. Likely L, R, Sub, Center (Between the seats)?

If the above is true.

Center you can forget about... you'll have to combine L and R and run it to the Sub.
Click to expand...

I believe the crossover for the subowoofer is built-in. These Bose amps are also internally EQ'ed to make up for the 99 cent drivers. I wish I could see the manual to that SOS harness. Anyone have it?

You can't just combine L&R and run into the sub by a "Y" wire. Need to send the subwoofer a mono summed signal. You will need another $20 adapter.. LOL:

0001219.jpeg


So the signal from the phone should be split with a Y adaptor, one side fed into this then to the SOS sub input. The other side fed into the Left and Right SOS harness inputs.

This can be done by a $2 resistor too, but I am trying to avoid solder work for you guys.

Hrant said:
I am following this thread as much as I can, but let me ask a few simpleton questions:

If the phone is hooked to the radio without the 12V option, then wouldn't the Bose amps turn on when you turn the radio?

Not sure why one would bypass the radio on/off switch unless the "options" available through the aftermarket head unit is nullified when the radio is on? I thought if you create 6 files of music categories, the radio presets get you to those files no? Or was that an option only with a Grom or USA Spec ....... now you know why i am so confused!!!
Click to expand...

Hrant, we are talking about eliminating the radio. Building files into music categories and trying to control your ipod and iphone through the factory radio is not a great way of doing things. You should just be able to operate all of this in simplicity, just like you do your phone now. These Grom and US Spec adaptors and that radio are not just old school, they are inconvenient. For someone like yourself seeking simplicity, I'd advise against this stuff. You should plug in your phone and hit play. That's it. You want to change a song, you grab your phone and do it like you always do, not learn a bunch of new time consuming steps.

What we have on this thread is a better solution IMO.
 
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I can make a parts list and diagram for anyone confused. We are talking under $100 for all the parts you need to correctly have a jack that plugs into any phone and goes right to the stereo system, with automatic turn-on of the amplifiers. This is of course for you guys that insist on keeping the Bose system. None of this is needed with an aftermarket amp and some real speakers. But for guys that don't want to change things... this is a good solution.
 
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Better yet, put a kit and sell them. I am sure many of us - especially old timers who like simpleton solutions that work without learning yet a new geeky language - will jump on it! :tongue:
 
I bought a standard Honda radio harness and bridged the front left and rear left. Also bridged front right and rear right. Both feed into soldered RCA plugs. Therefore turning a 4 channel L/R/F/R system into a 2 channel L/R system.

Works fine. Audio volume is controlled via the phone just like you were listening to headphones. Bose amp trigger is the standard blue wire trigger on the Honda harness bridged to the ACC red wire. (The remote turn on box via the RCA signal is an interesting solution)

My only problem is the massive engine noise coming from a ground loop via the cig charger into my phone's micro USB. I'll have to find a better ground for the cig lighter.

total cost was under $15 not including my time. more important was cutting the weight from the factory cassette player.
 
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How did you "bridge" these channels? Is the volume good? What's your phone?

So are you not feeding the sub or the center then? Cigarette lighters are actually a terrible place for power I'm not surprised of the hum. Ground that and the radio at the same point.
 
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