Switched and unswitched +12v sources for DVB-T.

[Cupra]

I took a feed from the passenger foot well when installing my kenwood

[HPsauce]

Originally Posted by HPsauce

There may be some confusion due to "mirroring" but I'm going by the actual (tiny) pin numbers moulded onto the socket.

And indeed there is.
I should have looked at the plug on the lead in the boot as well, that clearly only uses two of the three connections on the middle row, so my number 6 (blue) is unused too.

So Notorious' diagram matches, but the numbers are a mirror of my plug. I'm now pretty confident what's what as these CD units have been unchanged for years.
My 5 green is power ground, 7 grey is constant +12v and 10 yellow is switched +12V.

Originally Posted by notorious

ELSA is the only reliable source of wiring information for particular car.

Yes, and I have it (thanks to John ) and will check. But it's not convenient to fire up at present and I'm also far from familiar with using it.

Originally Posted by Cupra

I took a feed from the passenger foot well when installing my kenwood

I'm hoping that this is all relatively low power so won't need that.

[HPsauce]

I've just realised that I've been slightly misleading and limiting myself by mentally referring back to my PF S8 which had RNS-C and analogue TV.
There the TV had a separate power supply and was the obvious route for interfacing DVB-T (and any other video input such as a reversing camera) to the RNS.

Now I have just a CD player, which appears to be totally driven by the cable from the RNS. Or if it isn't, it's just the unswitched 12V that is independent and there are completely equivalent connections available in boot or by the RNS-D.

So the DVB-T tuner and A/V interface can actually be mounted pretty much anywhere and obviously don't have to be together. The major factors will be convenience of installation and access for operation (TV remote mainly) and whether any cables need extending.
It could all be mounted in/near the glovebox for example, with just a thin aerial lead to wherever that is best sited, though the aerial also uses 12v power (fed up the cable).

[HPsauce]

Just to update this, I've patched in to the CD lead near the back of the RNS-D and taken "permanent" and "switched" 12v supplies from there.
The switched supply does indeed only come on if and only if the RNS is on, irrespective of the ignition key. Exactly what I want.

And as a bonus, I've discovered that the AV interface box I have, which "says" it needs a permanent 12v supply to retain settings, in fact is happy to have that feed switched too.

[notorious]

good man

[HPsauce]

Now I just need to patch in to the CD lead in the boot to get outputs for the same switched and unswitched supplies and verify them.
I'll probably do that on the CD changer fly lead (rather than the loom) as I can dismount it easily and bring it indoors to work on.

[HPsauce]

Originally Posted by HPsauce

Now I just need to patch in to the CD lead in the boot

Sadly, having done that it doesn't work as expected, BECAUSE the diagram I was using (attached) is INCORRECT.
In fact, certainly in my car and I would guess many (all?) others the switched and unswitched power pins are reversed. I have confirmed this by careful testing, but only after soldering and taping up all the wiring.

In the diagram (which is a mirror of the CD changer fly lead socket) pin 6 is switched 12v (on when RNS is on) and pin 11 is permanent +12v. Earth/ground on pin 8 is correct.

In the CD changer fly lead these pins are numbered/coloured as follows:
Switched 12V - pin 7, GREY
Permanent 12V - pin 10, YELLOW
Earth/ground - pin 5, GREEN

Hope this helps anyone who decides to tap into these leads. I'm off to do some more soldering.

[notorious]

HP, but why didn't you use ELSA? That's the only source of information specific to your car.

[HPsauce]

Being lazy really, and initially I was going for both switched and unswitched so didn't verify enough when I decided I only needed switched.
Normally I'm very careful about checking things before committing to action; stupidly I skipped a check that only took me a few seconds today.

I already knew 100% what the wires were at the other end but didn't think it through as the connectors are different. In the end it took much less time to test with a multimeter than firing up a PC to look at ELSA.

[HPsauce]

Originally Posted by HPsauce

I'm off to do some more soldering.

All done; switched and unswitched supplies now available, tested and documented in the boot.
I was intending to watch the Rugby (RSA vs Scotland) but gave up after a few minutes as it's a slaughtering; so got the soldering iron and Certoplast tape out instead.