BMW-to-ISO connectors (and vice versa)

[goltho]

I'm swapping radios in the cars and - of course - they have different connectors. You'll see I've got the 17-pin round BMW connector with a secondary 10-pin female socket attached, and also a ISO A/B/C setup.

The first two pics below show what harnesses the cars have. The other three pics show adapters which I think would work. I'm unsure though about how to deal with a) the 10-pin female socket and b) the C-type ISO connector. I do not want to lose the paddle controls on the radio with the BMW connector which is being fitted to the existing ISO loom which I think is controlled by the C-type ISO connector(?). This is where I'm out my depth as I've no clue how to adapt that functionality. Any help would be appreciated, as always.

Dougie.

[Dorchester2]

Hello mate have a look on this thread post 52 & following.
I've encountered exactly the same problem and our nice mates Sjonnie and Roverlike were incredibly helpful:

https://www.the75andztclub.co.uk/for...=317803&page=6

and post 136 & following:

https://www.the75andztclub.co.uk/for...317803&page=14

Best wishes.

[goltho]

Originally Posted by Dorchester2

Hello mate have a look on this thread post 52 & following.
I've encountered exactly the same problem and our nice mates Sjonnie and Roverlike were incredibly helpful:

https://www.the75andztclub.co.uk/for...=317803&page=6

and post 136 & following:

https://www.the75andztclub.co.uk/for...317803&page=14

Best wishes.

Good morning Arnaud,

Wow!! That is some thread. I've scanned through it and will take the iPad out to the car in a while to begin comparing your notes with my wiring. I'm not installing an Erisin or other such unit so perhaps I'll be able to pick out the relevant facts and find a simple solution to my radio swaps.

Did you ever find out what the smaller 10-pin connector is for as shown on my second pic above?

Thanks again.

Dougie.

[Dorchester2]

Originally Posted by goltho

Good morning Arnaud,

Did you ever find out what the smaller 10-pin connector is for as shown on my second pic above?

Dougie.

Sorry Dougie I haven't the faintest clue for I didn't use it.

[Dorchester2]

Here is the one I've used:

https://www.ebay.fr/itm/255761701513...Bk9SR4T7_firYg

[SD1too]

Originally Posted by goltho

Did you ever find out what the smaller 10-pin connector is for as shown on my second pic above?

Hi Dougie,

According to the manual that could well be the "overlay harness" when a CD auto changer was fitted at the factory.
It's difficult to be sure of anything without knowing which original audio systems were fitted to the cars from which you've taken the connectors in thumbnails 1 & 2.

Simon

[goltho]

Originally Posted by Dorchester2

Here is the one I've used:

That's exactly the one I've found which comes near to being the same. However(!):- There are three extra pins on the donor car's 17-pin socket (so a total of 16 compared with the standard 13 pins used in the adapter). I've experimented this afternoon by reconnecting the radio I'm keeping (it's a Harmony from Philips) but with the small 10-pin black connector disconnected which sits in the larger plug. The SWCs continued to work without the 10-pin. That smaller connector is presumably indeed from the overlay harness which isn't connected to my existing car (thanks Simon/SD1too ) so we can forget about it.

So the extra 3 wires in the existing donor car's 17-plug are shown in the 1st and 2nd thumbnails below. The connector in the 3rd pic is the one I've ordered (for £5.99) which is identical to yours. The 4th pic is the standard R75 wiring on the 17-pin connector using only 13 pins, which corresponds to yours and to the one I've ordered. HOWEVER - you'll see in the first 2 pics that there are three extra wires (blue/orange, red/white and blue/?purple) which I've circled in red. My conclusion is that one or more of these are for the SWCs as it seems the Harmony did not use Canbus for SWC (what I found today plus I read it somewhere). I've checked voltage fluctuations on each of those three pins whilst the radio was turned on and there is a 0.1v flutter on two of the three wires when any of the SWCs is pressed (I forgot to note which, like an idiot). I've no idea whether this was significant or not though.

One more anomaly is the pin circled in BLUE. It's a black wire positioned where there exists a blank hole in the standard connector shown in the diagram on the 4th pic, plus the blank position has been moved to the other end of that row. No idea about that.

As far as I can see, I need to identify which pin(s) the SWCs are connected to on the donor car's 17-pin plug, in order to swap the Harmony over to replace the VDO CD413X in the new car which has ISO connectors including the C-type green connector which I believe feeds the SWC wires as per the 5th pic.

This may need reading a couple of times but I hope it makes sense. I don't really care about the SWCs not working on the donor car after the VDO is swapped into it. My aim here is to install the Harmony into the new car using the adapter you've used, but also to re-route what I presume are the SWCs on the green C-type ISO plug to the new 17-pin adapter. And for that to happen, I need to know where the Harmony is expecting those connections to be on the 17-pin plug.

Dougie.

[Roverlike]

Originally Posted by goltho

Did you ever find out what the smaller 10-pin connector is for as shown on my second pic above?

That 10-pin connector serves for CD-changer if your head unit supports CD-changer connection.

Regarding SWC, it is not using Canbus, it is connected to head unit and it is using resistance values on the pressed buttons to diferentiate functions. In some models of head unit you needed extra box which converts these resistance values into i-bus values which that particular head unit understands.

If nobody else provide you more info today, I will look into this when I am back from work in the evening.

[SD1too]

Originally Posted by goltho

I need to know where the Harmony is expecting those connections to be on the 17-pin plug.

Thanks Dougie, I can help now that I know I'm looking at Harmony wiring.

The steering wheel remote switch +ve is on pin 10 (blue/orange) of the 17 pin black connector. The -ve is on pin 17 (blue/purple).

Originally Posted by goltho

you'll see in the first 2 pics that there are three extra wires (blue/orange, red/white and blue/?purple) which I've circled in red.

Red/white is probably the panel illumination on pin 13, can you confirm that please Dougie? Your thumbnail pictures are too small and I can't enlarge them plus they're low resolution! If you can post the photo of the connector in full size using the mountain icon in the message box controls it will help enormously.

Originally Posted by goltho

One more anomaly is the pin circled in BLUE. It's a black wire positioned where there exists a blank hole in the standard connector ...

The only connection you're unlikely to have is pin 3, the telephone muting. However there's a black wire on pin 15 which is earth! I can be more sure with a higher resolution photo.

Simon

[goltho]

Originally Posted by SD1too

Thanks Dougie, I can help now that I know I'm looking at Harmony wiring.

The steering wheel remote switch +ve is on pin 10 (blue/orange) of the 17 pin black connector. The -ve is on pin 17 (blue/purple).

Red/white is probably the panel illumination on pin 13, can you confirm that please Dougie? Your thumbnail pictures are too small and I can't enlarge them plus they're low resolution! If you can post the photo of the connector in full size using the mountain icon in the message box controls it will help enormously.

The only connection you're unlikely to have is pin 3, the telephone muting. However there's a black wire on pin 15 which is earth! I can be more sure with a higher resolution photo.

Simon

That's great Simon, thank you. I've retaken the pics and uploaded them onto my server so they're clearer.

I've also enlarged the C-type ISO from the new car connectors as you'll see below. Rave shows those two wires on the green connector coming from the SWCs on the VDO CCD413X wiring in that car, so I'm assuming they will have to be connected (in whichever permutation) to pins 10 & 17 on the 17-pin adapter?

I'm concluding that the standard adapter I've ordered will have to have pins 10 & 17 added and wired for the SWCs, but the dimmer/backlight pin 13 will probably work off the bat. What's further confused me is that standard connector diagrams (see last pic below) number the adapter pins from 1-13 and not 1-17!