bezzal 1 Report post Posted October 29, 2008 I have done a bit of searching and from what I can gather: I have an OBC that does pull up light faults so I should use an adaptor. I realise though if I splice into the harness before the voltage measuring thingy, it wont effect this. But this means runing the wires to under the dash board. Sounds like it would be a lot easier to use the adaptor. I haven't as yet found where to wire the adaptor in how ever, is it self explainatary once you have the adaptor? I sometimes get stuck having to pull a trailer with the BM, and not the pajero so it would be good if I could get the lights hooked up. It alraedy has a tow bar. Your feed back is appreciated. Quote Share this post Link to post Share on other sites
jochen 4 Report post Posted October 29, 2008 Just use relays The extra load of a relay coil (ie: very very little) on the individual circuits won't upset the light bulb monitoring. A lot of auto sparkies use this approach, means they can use garden-variety automotive relays, and don't have to get any special BMW parts. Of course, using the relay method means you have no light-bulb monitoring of the trailer lights. If you use the original BMW trailer light module then you will have proper working light-bulb monitoring of the trailer lights. Quote Share this post Link to post Share on other sites