2018Plaptor

Hi all,
I'm new to the forum but not new to F150s: I recently replaced my old 04 XL with an 18 Platinum, quite a difference ;-)
The company that handled the import stuff messed up the trailer wiring for the EU connector: Trailers are not detected, which is quite annoying. Before I take everything apart and rewire it: Could someone please let me know how trailers are detected by the TBC?
Thanks in advance, Gunnar

bcb97

Just out of curiosity, if they damaged the vehicle then why are they not taking care of it? I see your in Germany so taking it to the dealership probably isn't an option.

RL1990

I'm not going to be much help since I don't fully understand the system; but as far as I know connector at the back of the truck is simply an input to the trailer control module. When the module senses an electrical load from the connector it knows a trailer is connected and takes over. First check the trailer wiring to make sure the lights work. Also does the wiring on European trailer connectors match North American wiring. Your owner's manual tells you which color wires correspond to the connector on the truck. Lastly you may have to simply re-enable the module instead of messing with the wiring. Call Ford Europe customer service for help.

Ricktwuhk

Right. When a trailer is plugged in, and then you step on the brake to put the truck into Drive, the truck detects that current is flowing back to the trailer's lights. That's why people who plug in anything to the trailer plug (like a light bar) get a message that the trailer is connected.

I think if you pull a wiring diagram for the F-150 harness, and then map each wire for the "EU connector", you should be able to figure it out.

2018Plaptor

Thanks for your answer and sorry for not providing all neccessary information.

The truck was imported from the US and registered in Germany by a Belgian company. So Ford was not officialy involved. The import company technically did nothing wrong: They simply added an aftermarket trailer connector. This type of connector is built for cars without any trailer connector, so it taps into the rear brakelights, turn signal and so on.
The annoying thing is that even though the truck has a TBC, trailer BLIS and so on, since nothing is wired into the trailer connector, all those features are not enabled because it doesn't detect the trailer.
My plan is to rewire the EU connector to the correct wires in the US connector harness, so that it will sense load when a trailer is connected. If load on the brake light connector is all that's needed, then I'm perfectly fine. If (for example) load on a electric brake wire would be needed, I'd have a problem since we do not have electric brakes... But based on the information from RL1990 and Ricktwuhk I'll give it a try and wire it the way it should have been done from the start ;-)

Thanks everybody, I'll let you know how things worked out....

flyinghappy

It does not require an electric break. My little boat trips it fine, I don't even have a TBC on my truck. As long as the lights are drawing current, it should detect it without a problem (once you get it wired into the trailer wiring instead of the truck lights)

BlueSpark

I think this question is worth digging into a little more.

On some threads, posters claim that tapping into the trailer reverse wire (for aux back up lights) trips the BLIS sensor, other call BS on that. So, what exactly *will* trip BLIS? A voltage drop? Current draw on a particular wire or combination of wires?

Let’s do a little better than SWAGs

rider_marc

My little utility trailer (no brakes) is enough for the F150 to detect a trailer. Also, I seem to recall reading something (maybe in the owner's manual) about connecting a trailer harness to the trucks brake/tail lights is not recommended.

acdii

Whether or not power is applied to the tail lights, there is resistance in the circuit through the filament. This is what is detected when a trailer is connected via either the braking circuit, or the running light circuit(most likely the brake light circuit). Tapping into the tail light circuits on the truck will not work since they are separate from the trailer connector, these circuits are isolated to prevent damage to the trucks CANBUS and other modules in the event the trailer has a short.

Isn't there an adapter to connect the US 7 pin to whatever is used in EU for trailers?

Ricktwuhk

IMO, nothing "trips the BLIS sensor". BLIS is disabled when a trailer is attached. If you attach wires to the trailer harness (including the reverse wire), and the truck senses the load, then it signals that a trailer is connected and BLIS is disabled.

If I were the OP, and if the truck's original 7 and 4 pin connectors are there, I would simply buy the adapter that goes from those to the EU standard. Failing that, I would search for a harness that can plug into the Ford harness connection wired properly.

I would then remove all the wiring that was done by the import company, since they clearly didn't know what they were doing.