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Discussion Starter · #1 ·
I setup the WDH with the Metris to tow our camper (~3600 lbs). Knowing that I would still need to add a brake controller, I cautiously took a short drive around the block to make sure the hitch was setup properly. I left myself plenty of stopping distance knowing the trailer brakes would be inoperable. To my surprise there was no feeling that the trailer was pushing the Metris when braking. In fact, it felt as though the trailer was dragging the Metris ever so slightly only when braking. In all of my research, there is no mention of whether or not there is an integrated brake controller so I assumed there wasn’t. I did some looking around the 7-pin connector and the diagram on the flip-up cover shows one of the pins is for electric brakes. Looking at the wires on the backside, there are 7 and 3 of them are a larger gauge. In my opinion the 3 that would require a larger gauge would be ground, +12 for battery charging, and electric brakes. I took some photos but it’s difficult to see all of the wires. There are definitely 7. 4 in a top row and 3 in a bottom row. I’m going to contact my MB dealer tomorrow and have them start investigating whether there is a brake controller.
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There is not. If you have the PSM ED5 on the 2018, there is an accessible "brakes activated" signal that works with the CAN bus. I have no idea whether it is pre-wired to the hitch connector, but I doubt it as the addition of the feature was noted for MY2019. The 2018 DOG says:

"YOU WILL NEED PSM (ED5) IF:
Your client plans to install aftermarket electrical equipment and needs the signals to trigger certain functions such as:
ƒƒ Vehicle status - Terminal 15 (ignition signal), Terminal 61 (engine running signal).
ƒƒ Light status - Light switch and steering column switch requests (e.g., high beams, turn signals, low beams, front fog lamps, etc.), upper control panel hazard
warning flasher, external locking.
ƒƒ Windshield status - Front and rear wipers, windshield and rear window heater.
ƒƒ Central locking - Doors open/closed, unlocked/locked.
ƒƒ Chassis CAN information - Wheel speed, speed, engine speed, cruise control operation, brakes activated, transmission, clutch information, steering angle, speedometer information as per the FMS standard."

The 2019 DOG describes one of the 2019 "highlights" as:

"ƒƒ Trailer brake controller connection will be part of the vehicle standard in combination with the code E58 (no additional sales code)
ƒƒ Trailer brake controller connection will be standard within the code Q24 with no additional sales code"

Q24 is the hitch option.
 

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Discussion Starter · #4 · (Edited)
I do not have a PSM, was told it’s not needed when ordering. I have the EK5 and the aux battery. So I did some more investigating and ringing out wires. There is definitely a wire in the terminal labeled “electric brakes” at the 7-pin trailer connector. It is black with a blue stripe, looks to be 14 gauge. I traced it up to the right rear compartment where the jack is stored. It goes through a single wire connector and continues as black/blue up the right-rear pillar towards the roof. That’s as far is I got. It would be nice to know if this heads to the front dash. All of the other wires go to a common connector into a control module in this jack compartment.
 

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I do not have a PSM, was told it’s not needed when ordering. I have the EK5 and the aux battery. So I did some more investigating and ringing out wires. There is definitely a wire in the terminal labeled “electric brakes” at the 7-pin trailer connector. It is black with a blue stripe, looks to be 14 gauge. I traced it up to the right rear compartment where the jack is stored. It goes through a single wire connector and continues as black/blue up the right-rear pillar towards the roof. That’s as far is I got. It would be nice to know if this heads to the front dash. All of the other wires go to a common connector into a control module in this jack compartment.
The EK1 Body Builder Connector is unavailable with the PSM.
 

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" There is definitely a wire in the terminal labeled “electric brakes” at the 7-pin trailer connector. It is black with a blue stripe, looks to be 14 gauge."

Interesting... Is there a voltage on that terminal when you apply the brakes? (You may have to have the trailer connected so your van knows that it is there). If it's a full 12 volts, it's probably just a signal for a brake controller. If it were connected directly to your trailer brakes, they would probably lock up if it can supply the current.
Without some way of adjusting the voltage (i.e. using a controller) I can't see that it would work.
 

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There is not. If you have the PSM ED5 on the 2018, there is an accessible "brakes activated" signal that works with the CAN bus. I have no idea whether it is pre-wired to the hitch connector, but I doubt it as the addition of the feature was noted for MY2019. The 2018 DOG says:

"YOU WILL NEED PSM (ED5) IF:
Your client plans to install aftermarket electrical equipment and needs the signals to trigger certain functions such as:
ƒƒ Vehicle status - Terminal 15 (ignition signal), Terminal 61 (engine running signal).
ƒƒ Light status - Light switch and steering column switch requests (e.g., high beams, turn signals, low beams, front fog lamps, etc.), upper control panel hazard
warning flasher, external locking.
ƒƒ Windshield status - Front and rear wipers, windshield and rear window heater.
ƒƒ Central locking - Doors open/closed, unlocked/locked.
ƒƒ Chassis CAN information - Wheel speed, speed, engine speed, cruise control operation, brakes activated, transmission, clutch information, steering angle, speedometer information as per the FMS standard."

The 2019 DOG describes one of the 2019 "highlights" as:

"ƒƒ Trailer brake controller connection will be part of the vehicle standard in combination with the code E58 (no additional sales code)
ƒƒ Trailer brake controller connection will be standard within the code Q24 with no additional sales code"

Q24 is the hitch option.
Could you help me out. I have a 2019 metris. I know they include the brake controller connection. But I can not find any more info on it. I just installed oem hitch. And I found tons of article on this forum for 2018 and prior brake controller articles, but very few mention ourbrake controller options for 2019 later. Is the trailer recognition module included? Or do I still need one. Or does it just provide and brake controller wire factory that sends the signal for a brake controller. If that’s the case what does that do for me in terms of brake controller options. Can I go with an aftermarket now? I prefer going oem, but I want to avoid having to have MB dealership program the trailer recognition module. Maybe the 2019 is programmed for a plug and play? Any help is greatly appreciated. I have 2019 worker passenger with an oem trailer hitch installed my self. Debating what options I have for the wiring and brake controller setup. Thanks!
 

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If you don't have the factory installed hitch, I'm not sure the wiring or CAN Bus programming will be there. Over my head.
 
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