So are gou outting a colored light in or a clear light? I wondered about putting clear lights inline with the trailer and help give some extra interior lighting.
And do you need to just instsll one set of lights to meeet voltsge check ok or do you need a set PER light purpose (ie brake/turn signal/park lights?

if my spelling sucks in this post its cause im typing on a tablet.

Thanks for the offer Clockwork - all good mate.
I think it would have been too hard to adapt the connector to our plug anyway, so I'm happy with my decision to simply install some 'old style' trailer lights.

Initially I thought about just getting a pair of clearance lights, however when re-thinking the whole situation I figured it would probably NOT fix the problem, so decided to purchase a pair of tail lights with all features (indicators, tail and brakes). They should arrive in a few days (eBay purchase) and once installed, I'll report back on the outcome.
The trailer did come with a couple of LED clearance lights, which will remain, so I'll end up with a combination - should look like a bloody Christmas tree when all is done...

ok.
so yeah you're doing a whole tail light/park light/signal light combo... thats the only way I figure this would solve the Check Trailer Lights error.

I have separate LED signals, tail lights and reverse lights...so its smarter for me to try a wire harness than replacing three separate light units.

Yes Clockwork - I'll be doing more or less a direct replacement (same shape/size) combination tail light with incandescent bulbs, which should sort out the dramas. These are becoming quite difficult to source now, as everyone seems to be selling LED's at a fraction of the cost of the older style lights. That said, the replacements have much better quality lenses than the cheap Chinese LED's that came fitted to my new trailer.

Update to the story.... New tail light assemblies with incandescent bulbs arrived in the mail finally. I tried to salvage the LED tail lights fitted to my new trailer, but the wiring to them had no slack and lenses could not be parted from the body of the light assemblies - glued on, as was the cable into the rear of the lights. Ended up squeezing a pair of side cutters behind the lights and snipped them off, leaving a very modest amount of wire/cable to solder to.

What a bloody drama. Looks like the lights were fitted with cable glued through back directly to circuit board, then the cables were chased through the box chassis rails, with no access holes. After pulling what's left of my hair out, I finally managed to solder some additional cable to each side and installed the new tail lights, which fit perfectly as they're the exact same size as the Chinese LED's. I'll now fit some clearance lights to the sides of the trailer, as there are only reflectors.

This may all sound a bit anal to some of you, but I want to be seen. Sadly there have been no less than 9 fatal car accidents in our region in the past two weeks...mostly idiotic choices made, resulting in catastrophic outcomes. Nonetheless, I'll do my bit to avoid some drongo running me off the road unnecessarily, by illuminating my rig like a Christmas tree.

It's been a week of car repairs and I now appreciate the relative ease of working on the E53 after having to replace an alternator on our 'cleaning van' (Opel/Holden/Vauxhall Combo Van). That little job took no less than 7 hours and involved the removal of not only the exhaust, half the intake system and the alternator mounting bracket, but finally discovered the only access point to get the bloody thing in/out was to remove the inner wheel splash guard and squeeze past the brake line. I'm over car repairs for a while I can assure you. That said, I was quoted $1100 for this 'little job' and managed to get away with it for the cost of an aftermarket alternator ($225), frustration, swearing, lots of coffee and some skinned knuckles...

Thanks once again to everyone that offered advice and guidance. If I still get an error message when I finally plug the trailer in to the X5, I'll cry a river of tears, but I'm pretty confident it'll all be okay now (moment of truth will be tomorrow)....;)

Looking at your photo, you dont seem to have the reverse terminal connected?

Does this work with LED Lamps?

Drongo :thumbup:;)

Correct - that's the point. The trailer has no reverse lights so I have to fit the two diodes as shown to fool the bulb check monitor the car. Without the diodes I have a "Check Trailer Lights" warning on the dash when a trailer is connected.

And while this will "work" with LEDs (meaning the trailer LEDs will light up) it won't fix the dash warnings - you WILL get with LED trailer lights - fixing that issue requires either a trailer isolater circuit or resistors on each LED trailer light.

I avoid aftermarket LEDs anywhere on the e53 or on my trailers because of these issues - they're just not worth the hassle (to me).