Bluetooth module wiring

[Joner1983]

Hi all
I'm attempting to fit an aftermarket bluetooth module to the kenwood cassette player I have in my Cavalier V6. It seems like a decent idea, you plug it into the cd changer plug in the back of the stereo then wire it up with a 12v 'acc' (which I assume is ignition live) and a ground. I'm using solderless T tap connectors which is fine for the ignition live but the ground is far too thick. Can I just cut the module ground into one of the smaller speaker ground wires? Cheers

[Robsey]

No - the speaker ground is not vehicle ground.

You will always see radio installation manuals say -
Do not connect the speaker negative wires to the vehicle ground.

If it is a ground wire, connect it to a metal part of the vehicle body.
Or look for a fattish brown wire.

Vauxhall ground wires are brown.
Battery live are red
And ignition live is black.
Ensure you have a fuse in the supply wire.

[Joner1983]

Thanks for that Robsey, that's a great help.

To save cutting into things I might just run a seperate ground cable from the bluetooth module to the bunch of grounds on the wing, if that'll work.

What rating of fuse would I want for the live?

[Robsey]

That should be written on the paperwork supplied with the bluetooth module.

If in doubt, tell me the module details, and I will see what I can find out.

I presume it is a media streaming bluetooth unit.
Not to be confused with a phone bluetooth, which tend to be mono only.

The ones that I have seen online look like only low power units -they all quote functionality, but no useful info.
Looking at the size of the unit - I suspect less than one amp.
The fuse is to protect wires, not the module.

So easy to wire in -
Confusingly, aftermarket colour schemes always contradict the usual vehicle manufacturer din standard colour scheme.

Your ignition live wire -
Bluetooth unit red wire.
Vauxhall black wire.

Your ground wire -
Bluetooth black wire.
Vauxhall brown wire.

Most Nokia / Parrott and Bury car kits just piggy-back the wires from the radio connector.
No doubt you have seen the SOT leads online and in Halfords.

[Joner1983]

I didn't get any paperwork with it. It's a chinese Ebay special with a simple drawing showing what the wires do

[vectra1903]

On my Grundig SC303 the speaker ground is shared with the main ground.

I have my radio modified with this module and I have some tips.
If the audio signal ground in your radio is shared with the ground of this module you will most likely get an annoying whining noise or interference. This can be fixed with an isolating DC-DC converter but you have to be absolutely sure it's a 12V to 12V converter. This is the only thing that works, ground loop isolators don't work if anybody wants to suggest this. I have a B1212S-1WR2 converter installed with my module. You have to be absolutely 200% sure with the pinout when you're wiring it in as one mistake will disable your radio with some smoking and bad smelling special effects.