987 Boxster head unit swap - power problems?

[tomtom]

I'm trying to swap my CDR24 unit for a Pioneer SPH-DA120. I bought the CT20PO02 harness adaptor.

I can't get the Pioneer unit to power up on ignition (or at all actually). I suspect the switched 12V is where the problem lies - we verified we've got 12V from the 12V constant feed, all the way to the head unit, but the switched 12V doesn't seem to get anything, even with the ignition on. I've included some pics below to show how things are connected up, in case anyone can spot an obvious problem...

Thanks in advance!

[tomtom]

Oh yeah, my car is super basic in entertainment terms. No Bose, no amp even.

[jakesmith]

You need to run your own switched feed from the fusebox, the one that appears to be a switched live doesn't work as the PCM takes a signal from the MOST ring to power on & off.

So buy a piggy back fuse circuit adder, Make sure you buy the right sized one for the fuses in the fuse box can't remember if they are full sized or mini blades and then just run a metre of cable up into the back of the console

Halfords sell them

Buy a £10 multimeter, touch the negative to ground on the car & experiment with different fuses turning ignition on & off to find one that is ignition switched, ie +12v with the key turned and 0v when key off. Hint you can do this witout removing any fuses as the top of the fuse has a tiny conductor bit that you can touch the probes of the multimeter with

[gsewell]

You need to either get a switched feed from an empty fuse and run the cable over, or get a campus adapter that can provide the switched feed plus reverse and a few other functions.

[jakesmith]

gsewell said:

get a campus adapter

CANbus LOL
Yes you can do it that way, I couldn't get the Connects2 one to work in my R8 and ended up binning it after 2 hours of fking about
Simple piggy back fuse holder from a switched live in the fuse box is my recommendation & add CANbus later when you know it's all working. You can get reverse from the light anyway for the Pioneer head units

[tomtom]

Aha, thanks. I had read about this but for some reason thought it only needed running from the fuse box if the car had the amp, to wake the amp.

How does the CDR24 work then? Where does it get its ignition source from, as the unit doesn't work with the ignition off as far as I remember?

[jakesmith]

Think the car's canbus loop has an 'ignition on / off' message that lets the cdr24 know whether it can turn on or not, one of a few things Porsche did to make it as annoying as possible to replace the head unit, including (on PCM2) annoying uneccesary latches and a secret screw on the side of the unit, the use of MOST for the amp, funny impedance speakers etc.

[tomtom]

I see. Mine has the 'security screw' that causes the alarm to beep when you lock the car, unless you've wound it all the way back in which takes ages using a fiddly little spanner.

I pulled the fibre optic cables off the back of my unit when I first took it out, weeks ago now, when I first tried to fit the Pioneer. I couldn't get them back onto the CDR24 when I put it back in, so I left them off. The unit works absolutely fine without, so it can't be getting the ignition trigger over the fibre at least(!).

[jakesmith]

Canbus isn't on the optics it's 2 little wires that are part of the sub harness