NC BOSE Atoto S8 swap

Technical Area Electrics & ICE
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  1. My model of MX-5 is: 2009 2.0 Sport
  2. I’m based near: East mids
  3. I’m looking for technical help or recommendations on: Atots S8 swpa for factory Bose

Hi all, Looking for any advice on my lack of sound issues, im far from an expert on electrics and Audio, but willing to learn(one of the motivations for buying an MX-5).

I’ve purchased an Atoto S8 (MS DAB) Unit to replace the factory Bose system. I’ve also picked up the Connects 2 CTSMZ012.12 adapter for Bose Amplified Mazdas and the CTMultilead for steering controls. I’ve been able to get the unit to power up but cannot output any audio. I’ve followed the guidance i can find as much as able for wiring/connections, but I’m either missing something or the unit is faulty.

Anyone with more knowledge/experience in this area or this specific setup with some tips would be greatly appreciated, thanks

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You have missed the “amp power up” connection.

Currently you will have a blue wire that powers the amplified aeriel.

That blue wire needs splicing in to and feeding to the amp switch on wire. ( Amp control 1J )

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Thanks, I have the Blue cable from 1J on the power harness, and one on the Atoto unit of same colour labelled Amplifier turn on, these are connected, but come from a separate connection, not the main power, maybe that’s the issue? I’ve highlighted in the image.

The only other blue cable is labelled Power Antenna, which is connected to 1J

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Did the head unit not come with an ISO harness to plug directly in to the connects adaptor ?

There should be very little wire splicing to do when connecting the head unit to the car when using a connects2 harness.
All most people need to do is add the extra amp control wire to the harness.

Back of car connector
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Metra connector - head unit side
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5

Yes there is an ISO harness with the unit, two in fact, but the other has different colour cables. I’ve used the one that matches up, which is circled green in my first post image, but there’s no blue/white cable as part of that, just a blue labelled antenna power.

The Connects 2 Blue/white cable from 1J has a different connector and doesn’t go to the ISO connection but a separate connection which feeds into a matching cable, which is the yellow hihglighted part.

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In order for the aerial and the amp to be switched on - you need the head unit to supply power to pins 1H and 1J in the car connector.

These connections are in addition to the power required to switch on the steering wheel control box.

I have fitted half a dozen units to MX-5’s with Bose and they have all been the same.

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Thanks for the guidance, much appreciated. So I guess my next step is to establish if the head unit is putting any power out on that amplifier control blue/white cable which hooks to 1J. Odd that it’s a separate plug to the main cable/ harness bundle.

If it’s not is there a recommended cable to splice into?

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The Atoto wiring diagram says that the blue is deffo an amp switching wire.

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That blue wire needs to power at least two items

  1. Pin 1J to power up the amp
  2. Pin 1H to power up the aerial

It looks like you have covered 1H by joining the blue to the blue/white

You now need to add another wire to that bullet joint - and feed it to pin 1J on the Metra Conector in the car loom.

The reason the blue is hanging loose is because some cars wont need to power the amp and you don’t want a live feed hanging around if not needed.

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Thanks Deano, excellent information..really appreciate it. I’ll be able to have another crack at this tomorrow. Changing a light bulb is about the limit of my prior electrical experience :grinning_face_with_smiling_eyes:

Just to check, when you say the blue is definitely an amp switching wire, do you mean the one I have labelled as Amplifier Turn On (+) ? (which is blue/white on my unit)

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yes - it goes 12v live when the head unit is on.

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Success, the wiring was right, thanks to your help and info, but there was a setting in the headunit menu that needed switching on to give amp power output…..was a little hidden away.

Now just need to figure out why the Connects2 steering wheel control adapter isn’t working.. do you have any info on that at all?

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Have you been in to the head unit menu and taught it what the steering wheel buttons should do ?

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