Brake controller for E70 experiences - Page 3

Mabuhay · #21 03-30-2009, 10:57 PM

Who's the blonde hottie (from a far) in the pic?

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tdg · #22 03-30-2009, 10:59 PM

I haven't actually picked up the trailer yet - not sure if the family comes with it...

xDrive35d · #23 03-31-2009, 01:36 PM

This is interesting. I'm picking mine up later this week and I'm having them install the hitch. I think pretty much all SUV's and trucks these days come with a trailer controller connector under the dash. I'm really surprised to hear BMW doesn't have one. After all, they talk about towing in a lot of their sales literature. A few things to consider. I don't think I would use a weight distributing hitch when they state specifically not to use one. It's just my guess (ASSumption) that there may be some concern with the additional stress this places on the frame. Weight distributing hitches transfer a fair bit if weight to the frame of the tow vehicle. Maybe it's not designed to take that type of stress. It acts like a lever pulling up on the rear of the frame (over the axle) and pushing down on the front axle through the frame. Basically using the rear axle as a fulcrum if I understand correctly. The other reason may just be that they have a program that cures trailer sway using the brakes (Trailer Stability Control). This is per the sales brochure. I have quite a bit of experience towing and I think towing anything under 6K (lbs.) is unlikely to cause any real sway problems. I will tow without any kind of weight distributing hitch and see how it works using the BMW trailer stability control.

Does anyone know what the "Single Wire (blue/brown) Trigger signal for Electric Brake Control Module" as described in the hitch installation instruction's does? Do you think it's just the brake light signal that brake controllers use to know when to activate? I just wonder why they would have that separate from the 4 wire brake controller connector that's there also.

Here's a link that has info on brake contollers including a typical wiring diagram:

Brake Controller's

Thanks for any info,

Dave

JCL · #24 03-31-2009, 05:41 PM

BMW doesn't design a trailer brake controller into the X5; see the posts above. There is a harness in the rear, but I understand you still need to run a wire to the front.

I think that the reason that BMW states not to use an equalizing hitch is because they have no experience with them, and have no control over how they will be used, hence a liability issue. Experienced drivers towing are accustomed to them, and they are essentially an unknown to the rest of the world. I would say that the equalizing bars reduce stress on the vehicle suspension, and have little if any effect on the chassis. There isn't a frame on the X5, as it is a unibody design, but the same principle carries through. They transmit a bending moment, but it is relatively small, only a few hundred pounds typically. The rear axle is not the fulcrum in that scenario, the front axle is (as the fulcrum is the lever point).

I don't think the trailer sway control will have much effect with very slight sway, it uses the dynamic vehicle sensors to sense when the trailer is taking over the vehicle, and damps it out with the use of brakes. In that sense, it will intervene similarly to ABS, and not be engaged constantly (although it will monitor constantly). Agree completely that with a light or medium weight trailer you don't need an equalizing hitch. Trailer weight distribution (correct tongue weight) matters more than anything else. I never towed over 5000 lbs, but that was fine without an equalizing hitch on an E53.

Good luck.

tdg · #25 09-26-2009, 04:38 AM

Sorry for the delay posting the photo - got this baby out 12 times this summer (10 3-day weekends + 2 5-day trips). I had no problems with power or the distibution hitch. I averaged about 10 mpg. I live near the mountains and those trips averaged about 8 mpg. All I can say - tons of power - no worries with sway - and looks pretty damn sharp. I did have to get the BMW custom mirrors which cost $280 CDN, as many of the after market mirrors didn't fit well... PS tailor weights 4600 lbs...

tdg · #26 09-26-2009, 04:45 AM

One more to better show the hitch arrangement.... the day it came home..

X5 Meister · #27 03-23-2010, 02:06 AM

Seems like as good as any place to post some complete instructions and other stuff for the E70 tow hitch (Class III). (I did the same for the E53 here (post # 55): http://www.xoutpost.com/bmw-sav-foru...llation-6.html)

Please note that both the US Hitch and the Euro Hitch must be retrofit coded. The Electric Trailer Brake Kit does not require coding.

If I find anything else I'll add to this post.

Attached:

1. US Hitch installation instructions - Date 12-2006 (p/n 71-60-0-413-359 NLA. Superseded by p/n 71-60-2-156-525 Retail $500.00)
2. US Hitch installation instructions - Date 7-2009 (p/n 71-60-2-156-525 Retail $500.00)
3. US Hitch installation instructions - Date 8-2009 (p/n 71-60-0-413-359 NLA)
4. Euro Hitch installation instructions - Date 3-2008 (in 2 parts due to board size constraints)
5. Euro Hitch installation instructions - Date 10-2009 (in 2 parts due to board size constraints)
6. Hitch Step instructions (p/n 82-11-0-417-602 Retail $79.00)
7. Electric Trailer Brake Kit installation instructions - Date 8-2009 (P/N 82-11-0-420-082 Retail $255.00)
8. Electric Trailer Brake Photo

bracoX5d · #28 03-23-2010, 06:02 PM

Quote:

Originally Posted by X5 Meister

Seems like as good as any place to post some complete instructions and other stuff for the E70 tow hitch (Class III). (I did the same for the E53 here (post # 55): http://www.xoutpost.com/bmw-sav-foru...llation-6.html)

Please note that both the US Hitch and the Euro Hitch must be retrofit coded.
If I find anything else I'll add to this post.

Attached:

1. US Hitch installation instructions - Date 12-2006 (p/n 71-60-0-413-359 NLA. Superseded by p/n 71-60-2-156-525 Retail $500.00)
2. US Hitch installation instructions - Date 7-2009 (p/n 71-60-2-156-525 Retail $500.00)
3. US Hitch installation instructions - Date 8-2009 (p/n 71-60-0-413-359 NLA)
4. Euro Hitch installation instructions - Date 3-2008 (in 2 parts due to board size constraints)
5. Euro Hitch installation instructions - Date 10-2009 (in 2 parts due to board size constraints)
6. Hitch Step instructions (p/n 82-11-0-417-602 Retail $79.00)
7. Electric Trailer Brake Kit installation instructions - Date 8-2009 (P/N 82-11-0-420-082 Retail $255.00)
8. Electric Trailer Brake Photo

Great stuff. One question is the controller easily removable when not in use? Or do you permanently lose use of the cup holder?

X5 Meister · #29 03-23-2010, 06:13 PM

Happy to help.

Take a look at the installation instructions and see what you think. My interpretation is that it's pretty well semi-permanent. If you cut the cupholder pad in half (which is optional to do) then it's certainly more permanent. Also you'd need to remove or relocate the assembly when you are not using it.

Quote:

Originally Posted by bracoX5d

Great stuff. One question is the controller easily removable when not in use? Or do you permanently lose use of the cup holder?

bluvalley · #30 03-24-2010, 10:24 PM

Great instructions, thanks.

I wish the dealer had them when I had mine installed, they did a good job but I had to explain it all to them.

If you don't want to take up the cupholder, I placed mine on the dash to the lower left of the steering wheel, next to (and below right) of light controls. It's at a sharp angle but works fine.

Good luck,

James

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