Blinkers blink fast with the new trailer. Why?

[TowX]

Way back in '07 when I got my previous open deck trailer, the blinkers would blink fast, and all the trailer lights would flash every 10 seconds or when the truck was turned off. Dealer recoded it and everything worked just fine. And even a couple of rented uHaul trailers worked fine too.

Now with the new enclosed trailer, I have the same old problem back again. Blinkers blink fast, and all the trailer lights flack every 5 seconds or so, even when the X5 is running. I plugged my old trailer in (they're sitting side by side) and everything is normal.

The only difference I can think of is that the enclosed trailer has a lot more clearance lights than the open trailer. And the new trailer has LED blinker/brake lights while the open trailer has traditional dual filament bulbs. I know LED's draw less power and could cause this kind of problem. But if the X5 was coded for towing, why wouldn't it work for all trailers plugged in? I find it nuts that BMW would not make an electrical system for any type of lights.

As a simple check, I grabbed my ex's Explorer which has the factory towing package. Plugged in the open trailer and all works fine. Plugged in the new trailer and all is still fine. So the problem is the X5. My dealer is stumped and suggested that I'd need to recode each time I change trailers, which is not going to happen! And BMW NA was no help either.

Any thoughts or advice??

[admranger]

I think it has to do with the LED lights being lower resistance than incandescents. Don't know where I saw that though...sorry

[THK]

Purchase load equalizers to correct the resistance levels. Go on line and visit some of the LED sites or many motorcycle shop carry equalizers also.

[nom3rcy]

I went through exactly what you are describing, and I bought this: 7-Way to 7-Way Trailer Adapter for VW, Audi and Porsche Towing Trailers with LED Lights Valley Wiring V39010

Now it functions perfectly.

You can also buy it from a VW/Audi/Porsche dealer if you want to pay twice as much.

[JCL]

We had this discussion last year IIRC. Even had the same links to the LED adaptors.

http://www.xoutpost.com/bmw-sav-foru...-attached.html

One thing you could check before buying the module (even though it isn't expensive) is that the trailer ground connection to the vehicle is good. If you are relying on the hitch ball to provide the ground, that is what could be different between the two trailers. Run an extra ground wire just to test it to make sure.

[TowX]

I'd read the earlier threads but perhaps misinterpreted the reasoning. I guess my frustration is that I've never owned a tow vehicle in 30 years of towing that required different coding or different expensive adapters just to hook up different types of trailers. And I'd already called etrailer.com the other day to ask about the VW adapter and they said it would not solve the problem for the BMW, though it sounds like for nom3rcy it worked fine.

JCL- My first thought was to check the ground so I used my jumper cables to connect the tongue of the trailer to the hitch, and no difference. But thanks for the input.

I've got a pair of ballast resistors that I picked up online earlier this week, came yesterday. Haven't had a chance to install them, it's just to darn cold out to play with the trailer lights.

BMW zone service rep was at my dealer today so I drove over to see him. He said he's never heard of the problem but opened a PUMA case with NA to see what they thought. But he did say that my trailer control module was a way old version, and there have been revisions. He wondered if that's one of the things that may have changed. I'll know more late next week.

[nom3rcy]

You shouldn't be frustrated because our cars weren't designed to handle LED trailer lights. It is a very new technology, especially on trailers.

I went through all the same stuff you did, talked to the etrailer people, talked to local trailer people, the BMW dealer, independent shops and even Featherlite... trust me, all you need is the adapter harness and you'll be good to go.

For $25, it doesn't really get any easier.

[RickM5X3]

Great thread; helps me solve yet another problem/gremlin with my rolling sh&T show of a vehicle.

[TowX]

Originally Posted by nom3rcy

You shouldn't be frustrated because our cars weren't designed to handle LED trailer lights. It is a very new technology, especially on trailers.

I went through all the same stuff you did, talked to the etrailer people, talked to local trailer people, the BMW dealer, independent shops and even Featherlite... trust me, all you need is the adapter harness and you'll be good to go.

For $25, it doesn't really get any easier.

Thanks, I'll order one up to try. Need a few other things from etrailer for the new trailer anyway. I guess the only thing I'm unsure about is what effect the VW adapter has on the way the E53 stability control adapts when it senses a trailer is connected. If the adapter essentially tricks the light control module, does it also prevent the stability control from recognizing there's a trailer behind? I guess one way to know is this- does the adapter turn off the rear park sensors when connected like hooking up a regular trailer?

[JCL]

Shouldn't have any effect on TSC. Stability control module doesn't talk to the trailer, the vehicle just knows that something is plugged in.

All the adaptor is is a set of resistors to increase the load of the LED lights.