BCM Programming - Trailer Lights

[Querys]

Hello,

Does anyone know if it is possible to deactivate the brake lights for the Trailer wiring by programming the BCM with ForScan?
Due to German legal requirements we have a different setup for the trailer connector. This makes is mandatory to seperate the turn signal from the brake signal.
1 turn left
2 Rear Fog Light
3 Ground
4 turn right
5 positioning light right
6 brake light
7 positioning light left
8 reverse light
9 battery +
10 charge wire
11 fre
12 free
13 ground Pin 9-12

I want to avoid cutting wires, but if nothing helps, I will disconnect the wires from BCM to the relay and connect them instead to the rear vehicles turn signals.

 

[peterk9]

Have you checked your fuse panel layout in the Owner's Manual? There are several fuses that govern Trail Tow also shown as TT. Perhaps pulling those fuses may get you what you want?

Peter

 

[Querys]

Good idea, but unfortunately there are only two fuses for "right rear turn signal/right trailer brake/turn signal"
and "left rear turn signal/left Trailer brake/turn signal"

 

[peterk9]

Good idea, but unfortunately there are only two fuses for "right rear turn signal/right trailer brake/turn signal"
and "left rear turn signal/left Trailer brake/turn signal"

There are fuses in both the engine bay and cabin fuse boxes/ Did you check both of them?

Peter

 

[Querys]

In the engine bay there are some relais for the Trailer, but no fueses. The relais are directly conected to the BCM. Unfortunatly the Brake/Turn Signal for the trailer comes direktly out of the BCM. The "logic" is stored in the BCM.
If I do not convince the BCM, that I do not need the brake signal one the turn signal wire, I have to cut wires :-/

I already studied the wiring diagrams and it is relativly clear.

 

[sheltonfilms]

Make an adapter using a 2 to 3 wire tail light converter.

See this post:

Wiring US 4-Pole Trailer Connector to For Trailer with European 7-way | etrailer.com

 

[Querys]

Thanks shelton!
I just found that side some minutes ago and this would be the solution.
I will check tomorrow, if I can seperate the signal somewhere else, because the TT relay in the engine compartment keeps operating, even with activated brake. I will do some measurements tomorrow and will decide, what I have to do

 

[sheltonfilms]

I got curious on how this works and I figured it out. It's a logic based circuit.

LT output = LT input AND NOT RT input

RT output = RT input AND NOT LT input

Brake output=LT input AND RT input

 

[Querys]

I got curious on how this works and I figured it out. It's a logic based circuit.

LT output = LT input AND NOT RT input

RT output = RT input AND NOT LT input

Brake output=LT input AND RT input

sounds valid to me. Could be an issue with Hazard Lights? In this case the brake lights would flash? Furthermore how do they generating the Flash Frequency?
I assume they use some "ground noise" from the grounding pin? Otherwise the trailer would have another turn signal frequency than the car?
Anyway I ordered the converter at Amazon, unfortunately they need 2 weeks to deliver to Germany.
But maybe I will be able to measure something tomorrow which helps me understanding and avoid cutting wires or making modifications to the OEM wiring.

 

[sheltonfilms]

sounds valid to me. Could be an issue with Hazard Lights? In this case the brake lights would flash? Furthermore how do they generating the Flash Frequency?
I assume they use some "ground noise" from the grounding pin? Otherwise the trailer would have another turn signal frequency than the car?
Anyway I ordered the converter at Amazon, unfortunately they need 2 weeks to deliver to Germany.
But maybe I will be able to measure something tomorrow which helps me understanding and avoid cutting wires or making modifications to the OEM wiring.

Im thinking the same thing on the hazards. The signal delay is probably just a few milliseconds so it shouldn't affect the flash timing. Signal would just be passed through. I don't think it would act like a filter (smoothing) if that is what you are thinking.

Should be able to get a connector that matches the car and one for the trailer and then add the converter between the two. Then put it in a water proof box and attach to trailer. Wouldn't have to cut factory wiring then.

 

[Querys]

I have to install a German Conector at the car otherwise I have Use the adaptor every time. But I‘m okay with cutting the car wiring which is dedicated to trailer towing.
I have a solution now.
Cut the wires right before they are exiting the cars body and install the 2to3 converter. Afterwards add the new trailer module which comes with my German trailer wiring kit.

Last open question: how to deactivate the rear PDC when a trailer is connected. My trailer module support this an delivers a ground signal. My best idea: deactivate the speaker for rear PDC, this will keep the rear view camera alive.

 

[sheltonfilms]

Last open question: how to deactivate the rear PDC when a trailer is connected. My trailer module support this an delivers a ground signal. My best idea: deactivate the speaker for rear PDC, this will keep the rear view camera alive.

Not picking up what you are saying here.

 

[Querys]

OK let my use different explaination.
When attaching a trailer to the hook, the rear parking sensor will make alarm, because of an obstical right behind the bumper (the trailer).
to avoid this during backup with attached trailer, the rear park sensors will be deactivated by the my new German Trailer Control Module.
It delivers a "ground" signal with attached trailer. In German vehicles the Park Control Module has an input for this signal.

Maybe the US-Wiring already had support for this deactivation, but I do not know, which line will trigger the PDC off.

By the way: Today I installed the trailer wiring almost completly to the vehicle. But still have to wait for the 2to3 wire adaptor and I'm searching for the best and most durable connection to the battery. I recognized an open pin directly at the battery but I have to figure out, what kind of terminal I have to use for this.
I marked the connector on a picture I found on google

 

[peterk9]

OK let my use different explaination.
When attaching a trailer to the hook, the rear parking sensor will make alarm, because of an obstical right behind the bumper (the trailer).
to avoid this during backup with attached trailer, the rear park sensors will be deactivated by the my new German Trailer Control Module.
It delivers a "ground" signal with attached trailer. In German vehicles the Park Control Module has an input for this signal.

The rear park aid (sensors) can be turned OFF using the Information Display. Some later Explorers actually have a button on the dash to disable them. Have you looked into that?

Peter​

 

[sheltonfilms]

I don't recall having an issue when I attached a trailer. Maybe I just turned it off last time.

 

[peterk9]

I don't recall having an issue when I attached a trailer. Maybe I just turned it off last time.

Forgot to mention that the 'Default' is ON.

 

[Querys]

The rear park aid (sensors) can be turned OFF using the Information Display. Some later Explorers actually have a button on the dash to disable them. Have you looked into that?

Peter​

Hm have not checked that. Maybe I will attach a trailer first and will check, how it works.
Currently I have the front and rear bumpers disassembled to att all the wirings.

Does anyone have an idea about the Battery Terminal? I tried to google everything, but failed finding the right terminal for the connector.

 

[Querys]

yesterday I had the rear bumper re-assembled and tested the Rear PDC. Once you shift into R a small popup in the cluster will give you directly the option to activate or deactivate the rear PDC. So nothing to do for me on this item.
I'm still waiting for the 2to3 wire adapter from Amazon.com, right now it is in customs clearance.

 

[Querys]

Got the 2to3 wire adapter.
Unfortunately the hazard lights are still on the brake light.
So the logic in the black box is to simple for hazard lights.
The box is in this case not legal in Germany.

Any other thoughts?

 

[sheltonfilms]

Got the 2to3 wire adapter.
Unfortunately the hazard lights are still on the brake light.
So the logic in the black box is to simple for hazard lights.
The box is in this case not legal in Germany.

Any other thoughts?

You have a site or document that shows all the requirements for lighting for Germany?