A few months ago, I purchased a new Radio from FieroTom here on the forums, with the extra AUX port to connect to a trunk CD changer. Separately, I purchased some devices to take advantage of that 9-pin aux port, but haven't installed them yet.

First device: this auxiliary adapter and cable. It looks like this unit is powered from the radio, which is excellent, and should make my job easier...

However, the second device is where I need some help. I also bought this bluetooth adapter. Yes, in retrospect, there were probably better devices out there. However I've got a similar device in my daily driver and am fairly happy, but mainly simply familiar with it. I need a nice, hidden, switched 12v power supply under the dash. I plan on installing an outlet like this so I could easily swap-out the bluetooth adapter if needed.

However, that's where I'm stuck: What do I splice in-to?

My current thoughts, based on this information about the radio wiring harness would be to use the Power Antenna pin (Black connector, pin 8). I don't have a power antenna, so this should be empty currently. Furthermore, if I have a bluetooth connectivity issue, it would turn off and on with the radio, instead of the car.

Any thoughts, suggestions, comments, and dire warnings are very welcome.

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Seq

1987 Fiero GT : Information | Gallery

I might be wrong about this, but i think the power antenna feed is a low voltage "trigger" which should not be used as a power source. you could tap off the ignition power going to the radio or run a wire to the fuse box, put a spade connector on the end, and plug it into the place labelled IGN (in the box). Just a few thoughts ...

Why not just piggy back off the power wire to the radio?

You can use the power antenna turn on to trigger a relay that way when you turn the radio off it will turn off the blue tooth adapter
Wire pin 30 to the 12v constant on the radio 87 to the Bluetooth power 85 to power antenna lead and 86 to ground.

Or like stated above just wire the plug into the switched wire and ground of the radio

[This message has been edited by jb1 (edited 06-24-2014).]

I have an almost identical Bluetooth adapter that I mounted in the location where the stock rear window defroster is located. It connects to my phone which turns on the bluetooth each time I put it in it's car dock. I got another 12 volt outlet with a fuse in it and ran it behind the radio and under the dash to the ignition terminals in the fuse box. The 12 volt outlet charges my phone and runs the bluetooth. It's been working really well so far.

So I'm really starting from scratch here, having never done this before. After a nice evening with my service manual, I've been learning to read wiring diagrams, and found out that "spade connectors" exist, and are what I'm looking for. Those will simply slot into the extra connections on the fuse block. I didn't know this

There are six connectors on the fuse block. All are fused. I'm citing page numbers from the 87 Service Manual, applicable to the V6. The L4 had a few different diagrams. Service manual is worth the $90 to get the reprint from Bishko.

2x IGN

• Pages 8A-10-3 and 8A-11-2
  
• Fused by the 10A Gauges fuse
  
• Hot in Run/Test/Start
  

2x BAT

• Pages 8A-10-0 and 8A-11-3
  
• Fused by 20A or 25A BAT fuse (block diagram shows 20A, wiring diagram says 25)
  
• Hot always
  

1x Radio

• Page 8A-10-3
  
• Fused by the 10A Radio fuse
  
• Hot in Acc/Run
  

1x Inst LP

• Pages 8A-10-0 and 8A-12-0
  
• Fused by 5A Inst LP fuse
  
• I'm a little unclear on this one. It's either Hot at all times, or possibly on with interior lights. It may even be connected to the dimmer, which would potentially cause variable voltage? I'm new to this...
  

IGN isn't on in ACC, which could be mildly annoying if I'm waiting in the car and want to listen to music. The Radio connector is on in both RUN and ACC, so it probably makes more sense for the bluetooth module.

I think I'm going to stick another connector into IGN to charge my phone, as well.

I still haven't figured out what to connect ground to, but that's for tomorrow night.

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Seq

1987 Fiero GT : Information | Gallery

quote Originally posted by seq: I still haven't figured out what to connect ground to, but that's for tomorrow night.

Anything metal. When working with Radio wiring sometimes randomly grounding *MIGHT* introduce noise into the system (normally changes with RPMs). Most recommend using a common ground for all stereo components (so in this case, try the same ground as the radio).

If yours not particular about how your wiring works they sell connectors that snap onto the original wire (it punctures the wire insulation) and allows a quick and easy connection for a new wire to piggyback off of. Puriests and OCD people hate them, but they get the job done quickly.