[jmciver]

Originally Posted by bagekko

There's a lonely 4 pin connector underneath the steering wheel lower dash cover, looks like it may be for the brake controller. Considering I have almost every option possible, not sure what else it could be for. Not a great picture but didnt have much time to grab a good light.

That is probably it. What I remember from the G05 forum on this topic was that it was a noteworthy PITA to find the corresponding male connector if you wanted to install a different brand brake controller - but it was found. Below is a thread from the G05 forum that talks about this, with pics of DIY harnesses...

https://g05.bimmerpost.com/forums/sh....php?t=1610985

[JerryW235]

That connector definitely is for wiring in an electric trailer brake controller. I followed the thread on the X5 forum, ordered the connector and pins from ECS Tuning, and used them to install a Redarc Tow Pro V3 unit. The first picture is of the Redarc wiring harness mated to the connector in the drivers side footwell. I did put plastic wire loom on it before the final install. The next pic is of the Redarc unit installed, under the dash, under the steering wheel, sitting on top of the housing for the drivers leg air bag. It's just stuck there with double sided tape. The last pic is of the control switch mounted in the dash. It looks a little out of place, but it really needs to be visible and accessible when in use. No real problems with the install, it works, no error codes or anything like that. Did have to do a little trimming with a Dremel to fit the switch housing in the dash, and to some plastic panels on the back side of the dash. (Could not get the picture to rotate, sorry.)

[elp]

Does anyone know if there is a break in period for a new X7 before I can use for towing? I'm thinking about towing a travel trailer around 4000 lb dry (~5000 when loaded) with tongue weight around 500 lb. Also I could not find any text on weight distribution hitch in the user manual, read somewhere that WDH are not ideal for unibody cars, is there any truth to this or worth of concern? Glad to see some other forum members have done it without issue.

[Wild Blue]

Originally Posted by elp

Does anyone know if there is a break in period for a new X7 before I can use for towing? I'm thinking about towing a travel trailer around 4000 lb dry (~5000 when loaded) with tongue weight around 500 lb. Also I could not find any text on weight distribution hitch in the user manual, read somewhere that WDH are not ideal for unibody cars, is there any truth to this or worth of concern? Glad to see some other forum members have done it without issue.

Well, for non-M cars there's an unofficial break-in period in general, the first 1,200 miles. Personally, I would not tow during that period.

I just ended my break-in period, so I'm having some fun!

[Toga_Lock]

With all of the problems there seem to be with finding the correct male plug for the brake controller, has anybody thought about changing out the plug on the X7 to a more universal one? It’s just pins in a plug, right?

[Wild Blue]

Originally Posted by Toga_Lock

With all of the problems there seem to be with finding the correct male plug for the brake controller, has anybody thought about changing out the plug on the X7 to a more universal one? It’s just pins in a plug, right?

You're referring to the wiring harness from the back of the tow hitch? Since BMW stopped making the X7 "pre-wired for brake controllers" starting in MY2021, I have no idea what wiring's in there anymore. That's why I went with the Curt wireless controller, just to make it easy.

If you're referring to the actual trailer plug into the tow hitch, it has both the standard 4-pin and standard round 8-pin plugs, both of which are universal. Pics from my road trip thread.

[elp]

Originally Posted by Wild Blue

You're referring to the wiring harness from the back of the tow hitch? Since BMW stopped making the X7 "pre-wired for brake controllers" starting in MY2021, I have no idea what wiring's in there anymore. That's why I went with the Curt wireless controller, just to make it easy.

If you're referring to the actual trailer plug into the tow hitch, it has both the standard 4-pin and standard round 8-pin plugs, both of which are universal. Pics from my road trip thread.

How is your experience so far with Curt Wireless brake controller? I just picked one up and tried it on my current vehicle (Acura MDX), and it felt a bit flimsy, the one I got doesn't have the rubber belt, wondering how much does it help. I worry it fall down or get disconnected on the road due to all the vibration.

[Wild Blue]

Originally Posted by elp

How is your experience so far with Curt Wireless brake controller? I just picked one up and tried it on my current vehicle (Acura MDX), and it felt a bit flimsy, the one I got doesn't have the rubber belt, wondering how much does it help. I worry it fall down or get disconnected on the road due to all the vibration.

TBH, I haven't used it yet. Likely this summer with getting out with my 4-wheeler. Holding it, it feels just a bit flimsy as you say, but not bad. I'm not familiar with the rubber belt you describe, but have heard that it doesn't stay in the plug socket very well. Curt may have added a retention belt because of it.

[jmciver]

Originally Posted by Wild Blue

TBH, I haven't used it yet. Likely this summer with getting out with my 4-wheeler. Holding it, it feels just a bit flimsy as you say, but not bad. I'm not familiar with the rubber belt you describe, but have heard that it doesn't stay in the plug socket very well. Curt may have added a retention belt because of it.

I have the Curt Echo unit and it works well. I have not had any issues with it staying in the socket when in use and I had no concerns with it coming out when I have towed. Not sure what this “rubber belt” being mentioned is either….

[columbia16]

Originally Posted by elp

How is your experience so far with Curt Wireless brake controller? I just picked one up and tried it on my current vehicle (Acura MDX), and it felt a bit flimsy, the one I got doesn't have the rubber belt, wondering how much does it help. I worry it fall down or get disconnected on the road due to all the vibration.

we used the Curt Echo all summer in 2020 - with our X5 - and Uhaul non-OEM 7 way (SEE PHOTO)

overall it works ok but the design of the clips for securing to your harness or to your female receiver on the tow vehicle are the worst -

please do yourself a favor and tape down the connections on BOTH ends - we have seen this fall off during our trips - and this is NOT safe as it shuts down the brake control and trailer tail lights

we just had a new WDH installed on our X7 and were told that the Echo clips securely into the factory 7 way plug -

FIVE minutes into our drive back home with our Airstream in tow - we lost connection with the brakes and caravan lights...

sure enough - the clip became loose and the Echo was falling out...

please use TAPE and secure it!

[jmciver]

Originally Posted by columbia16

we used the Curt Echo all summer in 2020 - with our X5 - and Uhaul non-OEM 7 way (SEE PHOTO)

overall it works ok but the design of the clips for securing to your harness or to your female receiver on the tow vehicle are the worst -

please do yourself a favor and tape down the connections on BOTH ends - we have seen this fall off during our trips - and this is NOT safe as it shuts down the brake control and trailer tail lights

we just had a new WDH installed on our X7 and were told that the Echo clips securely into the factory 7 way plug -

FIVE minutes into our drive back home with our Airstream in tow - we lost connection with the brakes and caravan lights...

sure enough - the clip became loose and the Echo was falling out...

please use TAPE and secure it!

Are you plugging the Echo brake controller directly into the OEM connector under the bumper of the X7 or are you using some type of extension chord jerry-rig setup like in your top picture? While I understand trying to be safe, but your unfortunate experience with the X7 and the Echo brake controller in your setup seems to be an outlier here. Again, in my experience, the brake controller clipped securely into the X7 and the connection from my trailer did not put any extra strain on the brake controller, thus further allowing the brake controller to stay secured in place.

[elp]

Thanks for the heads up! Have you tried using zip ties? I heard someone recommending that. I have not got a chance to use it yet but will be soon.

[columbia16]

Originally Posted by BdleyHT

This has been a helpful discussion thread. It's given me the confidence to try towing a 23ft airstream with my new x7 40i. The trailer is 6,000 GVW and estimated 700 lbs hitch wait, but seems like with a WDH I think I should be fine. Am I crazy? I have the factory installed hitch and m brakes. The manual says 600 lbs for hitch wait. I ordered the Curt echo wireless brake controller.

I also have a 2011 x5 d, which I've only used to tow a light hobie cat, but it sounds like it's pretty capable of towing more based on this discussion thread. It doesn't have the air suspension so I imagine I need to be careful with hitch weight for it.

If you plan to tow a 23ft AS - please avoid a traditional single ball hitch assembly and use a WDH


Andy Thomson at CanAM Rv in Canada has the most experience with nontraditional tow vehicles like the X7 and is a great resource!

sad reality: the factory BMW hitch receiver has a relatively low tongue weight capacity - (606 lbs) - you need a WDH for safety reasons.


this is our setup - we just picked up caravan today with our new WDH and bilateral sway friction controls.

Our caravan:

Airstream Caravel - 22FB -
Tongue weight - 525lbs (with LP and Batteries, unladen), laden - +700lbs
Base weight with LP and batteries - 4200 lbs (close to 5000 laden)

our X7 M50i with factory hitch
606lb tongue weight for factory hitch receiver is disappointing (why is this less than 10% of the stated tow weight of 7507lbs????)(the Range rover hitch receiver is the strongest of all non truck SUVs)

our WDH:

1. Eaz-Lift Elite Model
* 1200 bars
* two friction sway controls (does anyone have experience installing two of these, rather than one driver or passenger side control?)
2. Can-Am custom shank (to replace Eaz-Lift shank)
3. Reese WD Snap-up brackets (replace Eaz-Left snap u- brackets)

our brake controller: Curt Echo

our 2 hour trip back from Maine to Boston began with a complete failure of the Curt Echo - the clip to the factory receiver came loose -

as we learned in the summer of 2020 with our X5 and Curt echo - please TAPE the clips down!

otherwise the ride back home was great - vastly improved stability with the WDH compared to our single ball Uhaul hitch from 2020 with our x5.

[columbia16]

Originally Posted by jmciver

Are you plugging the Echo brake controller directly into the OEM connector under the bumper of the X7 or are you using some type of extension chord jerry-rig setup like in your top picture? While I understand trying to be safe, but your unfortunate experience with the X7 and the Echo brake controller in your setup seems to be an outlier here. Again, in my experience, the brake controller clipped securely into the X7 and the connection from my trailer did not put any extra strain on the brake controller, thus further allowing the brake controller to stay secured in place.

we are plugging the Curt Echo directly into the X7 OEM receiver - the Airstream technicians did the entire install and assured us the the Echo will not fall out...

5 minutes into our drive home today....DISCONNECTED! so we pulled into a rest area and taped the clips down...

the useless rubber strap should also be avoided -

Curt Echo - great concept, horrible design of the connectors - and I am worried that an unknowing tow vehicle will have a major accident when the controller disconnects from a broken or loose clip.

[columbia16]

Originally Posted by elp

Thanks for the heads up! Have you tried using zip ties? I heard someone recommending that. I have not got a chance to use it yet but will be soon.

Zip ties are also a great idea! i wonder if they would slide more?

we have used electrical tape (RED) so we can easily inspect these connections when stopping for fuel at night. it has never failed...yet....

[jmciver]

Originally Posted by columbia16

we are plugging the Curt Echo directly into the X7 OEM receiver - the Airstream technicians did the entire install and assured us the the Echo will not fall out...

5 minutes into our drive home today....DISCONNECTED! so we pulled into a rest area and taped the clips down...

the useless rubber strap should also be avoided -

Curt Echo - great concept, horrible design of the connectors - and I am worried that an unknowing tow vehicle will have a major accident when the controller disconnects from a broken or loose clip.

The issue sounds like it could be with the 7-way plug on your Airstream. When I first got the Echo, I initially had some intermittent electrical connection issues as you described. However, the 7-way plug on my trailer was faulty (failing due to previous wear and age). I replaced the 7-way plug on my trailer and have not had any electrical connection issues and the physical connection between the Echo and my trailer 7-way plug has been rock solid without issue (or tape).

Not saying the tape is a bad idea, but it seems like YMMV based on the 7-way plug from the trailer….

[columbia16]

Originally Posted by jmciver

The issue sounds like it could be with the 7-way plug on your Airstream. When I first got the Echo, I initially had some intermittent electrical connection issues as you described. However, the 7-way plug on my trailer was faulty (failing due to previous wear and age). I replaced the 7-way plug on my trailer and have not had any electrical connection issues and the physical connection between the Echo and my trailer 7-way plug has been rock solid without issue (or tape).

Not saying the tape is a bad idea, but it seems like YMMV based on the 7-way plug from the trailer….

good thought! but our airstream harness is fine - the echo popped out of our OEM 7 way on the bimmer...glad you have had good luck but controller is just a poor design with cheap plastic clips.

it is a design flaw that is waiting for a lawsuit.

[bono]

I am using Tekonsha 90250 Prodigy RF for the last ca. 15k towing miles (with X5, but this should not matter). Never had an issue.

[elp]

While we are on the Curt echo topic, in curious if it is possible to use a 7 pin extension cable between the car and the controller itself? That way, the controller can be mounted directly on the a-frame of the trailer.

[jmciver]

Originally Posted by elp

While we are on the Curt echo topic, in curious if it is possible to use a 7 pin extension cable between the car and the controller itself? That way, the controller can be mounted directly on the a-frame of the trailer.

Theoretically should be possible. If you search in this forum, I believe there is a member who did something similar to that with his X7 rig. Although, I believe the reason for the small extension was due to the Echo not communicating properly with a special remote camera setup installed on his trailer (that was powered via the 7-way plug).

[elp]

Originally Posted by jmciver

Theoretically should be possible. If you search in this forum, I believe there is a member who did something similar to that with his X7 rig. Although, I believe the reason for the small extension was due to the Echo not communicating properly with a special remote camera setup installed on his trailer (that was powered via the 7-way plug).

Interesting, I have to look it up and see if that's a common setup, if not, I'd much prefer to secure the controller on the A-frame for improved reliability and safety.

[jmciver]

Originally Posted by elp

Interesting, I have to look it up and see if that's a common setup, if not, I'd much prefer to secure the controller on the A-frame for improved reliability and safety.

I doubt it. IIRC, the company that made the camera system installed on his trailer supplied the special cable as the issue was unique to the camera system function, but did not affect the brake controller function (or lights) of the Echo and the trailer.

Honestly, I would not worry too much about it as the system as designed works pretty well. Most don’t have issues (based on what has been reported on the forums anyway). But if you want a bit of extra security, then adding some tape as mentioned above should be more than enough.