[KS_340i]

Hi

I am installing the westfalia towbar, with the westfalia dedicated 7 pin electrics kit (westfalia are the OEM towbar manufacturer for BMW).

However, the instructions refer to a "Bk/GN" wire in A174*14b module (which is the black green wire). I can locate the module and have done all the other wiring (page 29 of the atatched PDF link if anyone's interested!)

https://www.westfalia-automotive.com...3352391101.pdf


But, i have no black/green wire in that module.

i have located the pin assignments for that module, but would anyone know how to cross reference that to the coloured wires? I suppose i could look at each pin and trace them manually bu t wondered if there was a resource out there.

Or can anyone decipher the symbol used to see which wire i should use - westfalia make great kit but the instructions are something else!

[ian332isport]

As far as I can see, you don't connect that wire with 7 pin electrics, it would only be connected with 13 pin electrics.

If you look at the chart on page 3 of the Westfalia document, it shows that pin 10 (yellow wire) connects to terminal 15 on the car (Terminal 15 is ignition controlled live on a BMW). You only have pins 1-7, so pin 10 has no function.

Where did you see the reference to A174*14b? I can't see any terminal 15 connections on that connector. Pin 13 on A174*12b is terminal 15 though.

[KS_340i]

Originally Posted by ian332isport

As far as I can see, you don't connect that wire with 7 pin electrics, it would only be connected with 13 pin electrics.

If you look at the chart on page 3 of the Westfalia document, it shows that pin 10 (yellow wire) connects to terminal 15 on the car (Terminal 15 is ignition controlled live on a BMW). You only have pins 1-7, so pin 10 has no function.

Where did you see the reference to A174*14b? I can't see any terminal 15 connections on that connector. Pin 13 on A174*12b is terminal 15 though.

thanks, will check.

the reference to A174*14b is simply that this is the module being pointed to on the Westfalia wiring diagram. But as you say, it seems it wants a switched supply, and that is on 12b not 14b.

More confusing, happened to stumble upon BMW's own retrofit instructions which use a genuine BMW harness and it also wants one connection to pin 18 of 12b and another to Pin 12 of 14b (which is out right tail light?)!

but if i don't need it, maybe will try without connecting it and see what happens

[ian332isport]

Originally Posted by KS_340i

thanks, will check.

the reference to A174*14b is simply that this is the module being pointed to on the Westfalia wiring diagram.

Ah yes. I see that now.

More confusing, happened to stumble upon BMW's own retrofit instructions which use a genuine BMW harness and it also wants one connection to pin 18 of 12b and another to Pin 12 of 14b (which is out right tail light?)!

I suspect the BMW kit provides the full 13 pin connector though. Pin 18 of 12b would make sense as the brake light signal. Pin 12 of 14b would be the right indicator. I would expect a similar connection to pin 17 of 12b for the left indicator.

THIS is a good source of wiring info.

[jackstrath]

Il be doing this in time, good info here thanks

Just out of interest any reason why you went for the westfalia electrics? ( i had these on my x5 and 335d) but as far as i can see the PF jones electric kit is better as it turns off the reversing sensors and works with LED trailer lights

[KS_340i]

Originally Posted by ian332isport

Ah yes. I see that now.

I suspect the BMW kit provides the full 13 pin connector though. Pin 18 of 12b would make sense as the brake light signal. Pin 12 of 14b would be the right indicator. I would expect a similar connection to pin 17 of 12b for the left indicator.

THIS is a good source of wiring info.

Thanks - yes i had seen the pin allocation chart.

Have emailed Westfalia to seek their advice before doing any more.

[KS_340i]

Well, just to clsoe this thread

I called the supplier in the UK PF Jones - they said the kit simply needed a 15A switched connection. The point of this was to wake the unit up, as the module otherwise goes to sleep. Without it, nothing would work - and the unit sleeps otherwise it would drain the battery in a few days.

We identified that according the pin allocation for the module, the green/white wire on pin 13 of A174*12B was the right one - so i made a connection to that - and tested both the brake and switched connections and they seem correct so wired it up and powered it all on (had to buy a circuit tester for £5).

They said Westfalia usually get the wiring colours correct so unusual they got one of the wires wrong but hey ho.

All now is working as it should. Not tested yet in anger, will do that tomorrow.