[ktmsmr12]

***Updated with all required steps. Please review entire thread.***
Hey guys,
I bought a new 2019 X3 M40i two weeks ago and it had everything I wanted except the factory tow package. I've been doing a bunch of research and thought I could help others out. For starters, there really isn't a complete kit. LOL. There are however the individual kit pieces that combined, make the full kit. You end up with the following 5 part numbers.

Trailer hitch retrokit fit (actual hitch part) - part # 71-60-6-887-642 (on national backorder) $300

Wiring harness retrofit kit (includes harness and round 7-pin trailer plug and connector) - part # 71-60-2-458-028. $500

Trailer hitch/harness control unit - part # 71-60-6-889-584. $150

Lower trim cover for factory hitch vehicles - part # 51-12-8-094-861. $150

Lower reinforcement for factory hitch vehicles - part # 51-11-7-458-879. $50

Total for parts is roughly $1150.00

I'll be installing it myself as soon as the parts arrive. Hitch is supposed to arrive on 2/25/19. All other parts should be here this week.

I'm trying to understand if this can be coded via E-Sys or BimmerCode in Expert Mode. I'll share more as I learn more.

[skier219]

Amazing how expensive it is to retrofit what would be a $550 option on the vehicle!

I'd be curious to know if the lower trim cover is already painted. For $150, I suspect it's not, but you never know. If it's not painted, better figure that into the cost.

Other issue is that you'll probably have to remove/defeat the kick-to-open tailgate, since some of the sensors are where the hitch goes. I know that when you order the hitch from the factory, that feature is deleted from the car.

[CHATMAN]

Why not the Stealth version? https://stealthhitches.com/products/...5-2018-present

[ktmsmr12]

Originally Posted by skier219

Amazing how expensive it is to retrofit what would be a $550 option on the vehicle!

I'd be curious to know if the lower trim cover is already painted. For $150, I suspect it's not, but you never know. If it's not painted, better figure that into the cost.

Other issue is that you'll probably have to remove/defeat the kick-to-open tailgate, since some of the sensors are where the hitch goes. I know that when you order the hitch from the factory, that feature is deleted from the car.

Actually the lower trim piece comes in the same gray as all the factory ones so it comes ready to install.

Based on what I can tell, I'll still be able to use the kick to open function since I'm doing the retro fit myself and my car already has the kick to open.

I wanted the factory hitch so i would be able to keep all the factory towing functionality such as trailer sway control, disabled rear PDC, and a couple other features only available with the factory wiring and controller.

[couchgate]

Originally Posted by ktmsmr12

Actually the lower trim piece comes in the same gray as all the factory ones so it comes ready to install.

Based on what I can tell, I'll still be able to use the kick to open function since I'm doing the retro fit myself and my car already has the kick to open.

I wanted the factory hitch so i would be able to keep all the factory towing functionality such as trailer sway control, disabled rear PDC, and a couple other features only available with the factory wiring and controller.

Is it not possible to code these changes in with a 3rd-party hitch?

[ktmsmr12]

Originally Posted by couchgate

Is it not possible to code these changes in with a 3rd-party hitch?

If you use the factory wiring harness and factory trailer hitch control unit, you can probably use any hitch you want and once coded it will work properly. The hitch itself is just a piece of steel. I wanted the factory hitch though so it sat at the proper height and looks factory.

[jalanjohn]

I had the hitch installed by BMW dealer. I did not get the electronics as I will only use for a bike rack. 4 hours of labor to complete. The auto trunk open function no longer works.

[ktmsmr12]

Originally Posted by jalanjohn

I had the hitch installed by BMW dealer. I did not get the electronics as I will only use for a bike rack. 4 hours of labor to complete. The auto trunk open function no longer works.

Very nice! That should be a lot cheaper than the full install because the wiring harness and controller are about $650.

I downloaded the BMW factory directions for the install from one of the online parts dealers. It quotes 2.5 hours for the install without PDC and 2.75 hours with PDC. I assume you didn’t get anything coded since you didn’t install the electronics.

Did you get the BMW factory hitch? If so, did your dealer install the new lower trim piece made specifically for the hitch? I was told there are no factory hitches in the USA right now.

[ktmsmr12]

Update... got all the parts except the actual hitch. The lower trim cover comes painted the correct gray color and factory matches and obviously has the hitch and trailer connection cutouts.

The $500 factory wiring retrofit harness looks like it should cost about $50. Lol. Not much to it, but it does include the factory 4 and 7 pin connectors that directly snap into the hitch. Just waiting on the actual hitch now. Current eta is 2/25/19.

[ktmsmr12]

I finally got my hitch late last week. Installed it In my garage on Friday. You do not have to remove the actual bumper trim. Just the lower trim piece that surrounds the exhaust and hitch. It took me about 3-4 hours as I was going very slow to make sure I didn't break anything. Not difficult and could probably do in 90 minutes knowing how now.

You actually remove the existing metal bumper piece under the bumper cover and replace it with the hitch. Same four bolts (attached to frame) with new locking nuts provided in the retrofit hitch kit. I was able to do this without removing the actual bumper cover. It was a little tricky to remove, but not that hard. The new hitch was much easier to hang up into place as it isn't quite as deep at the factory metal bumper piece.

The new lower trim piece fits perfect around the hitch and exhaust. The lower two PDC sensors snapped right out of the old trim piece and into this new one. No tools needed.

I did remove both hatch kick to open sensors so that feature is no longer there. I probably could have kept them if I wanted to build a new mount, but I never used it anyway.

Everything is literally bolt on or snap in and the hardest part for me was routing the wiring harness back through the bumper grommet and into the passenger rear side panel. The passenger rear side panel is where the hitch electronic controller mounts and connects the hitch wiring harness to the factory tow prep wiring already in the car.

Hope this helps guys!!!

[stelthy]

This is awesome. I have a stealth hitch, and was waiting on installing it to try to use a factory harness.

Did you do any coding to enable trailer features yet?

[ktmsmr12]

Originally Posted by stelthy

This is awesome. I have a stealth hitch, and was waiting on installing it to try to use a factory harness.

Did you do any coding to enable trailer features yet?

I have not coded it yet. I have left the connector from the tow harness and hitch controller unplugged from the factory tow prep car wiring connector so I don't have any faults until I take the plunge and code it with ESYS. I'm new to coding and don't feel like I've got the needed knowledge yet to add the 3AC VO/FA and then add the AAG towing module.

[bmtespar]

I’ve played with this a bit on my previous x3. You can easily code the camera trailer zoom function to work without anything else hooked up. The other features, like disabling the pdc sensors and the blind spot monitoring will definitely take some more coding and hooking up the new modules. I don’t think you will throw any errors if you connect them now. The car doesn’t realize anything new has been added until it has been coded. Someone else mentioned something about sway control, that’s not a feature of the factory hitch.

[ktmsmr12]

Originally Posted by bmtespar

I’ve played with this a bit on my previous x3. You can easily code the camera trailer zoom function to work without anything else hooked up. The other features, like disabling the pdc sensors and the blind spot monitoring will definitely take some more coding and hooking up the new modules. I don’t think you will throw any errors if you connect them now. The car doesn’t realize anything new has been added until it has been coded. Someone else mentioned something about sway control, that’s not a feature of the factory hitch.

Thanks for the information. I thought when I added the 3AC option (VO/FA) and then "coded" the AAG module, it would allow for trailer sway control. I may be wrong.

I have searched the inter webs and cannot find the full process to add 3AC and the AAG trailer controller module. In fact I'm confused on ESYS in general. Some say you need ESYS launcher and a key generated, while others just say you need ESYS since you're not flashing the ecu's.

[bmtespar]

No problem. I hope it helps. The additional hardware and coding just puts the vehicle in towing mode which will disable rear pdc sensors and disables blind spot monitoring and I believe disables the remote and door trunk release (I not certain on this part). This is extremely handy if you have a bike rack and forget and hit the trunk button. Could save you from a lot of damage. The car will automatically go into trailer mode when you plug into the hitch connectors. Otherwise, you can put the car into trailer mode in idrive. The only other thing you will get is the camera zoom(camera looks more downward) for the trailer which adds little indicators to see where your hitch ball will be and then edge of your bumper.

[12v_dub]

Thank you for sharing, they must have made the trailer wiring harness just available as it wasn't for a long time. I will probably do this install soon as I also wish I had trailer package when I purchased my car.

[ktmsmr12]

Originally Posted by 12v_dub

Thank you for sharing, they must have made the trailer wiring harness just available as it wasn't for a long time. I will probably do this install soon as I also wish I had trailer package when I purchased my car.

Maybe so. Everything was in stock when I ordered except the actual hitch itself. It came from Germany and took about 10 days to get.

[skier219]

Thanks for the great writeup!

[ktmsmr12]

Originally Posted by skier219

Thanks for the great writeup!

Sure. If anyone has any additional questions, please feel free to ask or PM me. We are all here to learn from and help each other.

[ktmsmr12]

I thought I would make a final post on this to finish the X3 BMW factory Trailer hitch retro-fit kit. DIY.

So I have completed my retrofit factory hitch install with all the factory parts including the AAG hitch controller and oem wiring harness.
Vehicle is a 2019 x3 M40i

I have Esys 3.27.1 and psdzdata 4.15.31 on a native Win 10 Pro laptop. Using an approved ENET cable with RJ-45 connected to laptop
My X3 M40i is at I-step S15A-18-07-540

I'm not using any Esys launcher or token as I was told I didn't need it since I was just adding a factory option. (CONFIRMED)

Steps to code factory hitch and controller retrofit kit:

1. Make sure car is running. Using E-Sys and your ENET cable, connect to your X3 OBD2 port and expand the FA tree. (Lots of tutorials on the web in how to do this).

2. Add 3AC option code to VO FA. Make sure you save the original file and then save an updated copy. Add the 3AC option in the correct spot in the option list. Write new FA to car. (Lots of tutorials on the web to add a new VO code in your FA).

3. VO code AAG trailer controller ECU. Connect => Read FA (VO) => Activate FA (VO) => Read SVT (VCM) => Left-Click on AAG ECU => Click on "Detect CAF for SWE" => Select the CAFD from the Latest I=Level => Select OK => Right-Click on AAG (the ECU itself not the underlying CAFD) => Select CODE.

4. Now you need to VO code all ECU's that need to "see" the 3AC trailer option. Connect => Read FA (VO) => Activate FA (VO) => Read SVT (VCM) => Right-Click on the required ECU => Select CODE.

5. MANUAL METHOD - Repeat step #4 for each affected ECU that needs to know the trailer module exists (Head_unit, BDC body, etc.) You must repeat this for each affected ECU.

6. ALL ECU METHOD - You can also right-click on the root ECU folder and Select CODE. ***WARNING*** Make sure the car is not running if you do the "ALL ECU" method since it will try to VO code all ECU's including the engine ECU (DME). Ask me know I know. . If you use this method and code all ECU's, you will need to have the car in accessory mode (NOT RUNNING) and hooked up to an external power source (>10A battery charger or use jumper cables connected to another vehicle that is running) to make sure you maintain proper voltage.

7. You may see a bunch of warnings and reboots of systems as the VO code goes through each ECU. Don't freak out.

8. Once the VO coding of the needed ECU's is complete, read the E-Sys logs and make sure you have success message(s).

9. Disconnect Esys. Disconnect ENET cable from OBD2 port.

10. Power cycle your X3 and the warnings should go away.

11. Connect trailer connector to 4-pin or 7-pin trailer hitch connection on X3. Trailer lights work. Trailer camera zoom function works. Trailer sway control works. Rear PDC de-activates. Enhanced stability control activates. Blind-spot and side-collision detection are disabled.

12. Enjoy not spending $2500 for BMW to install your hitch and code your car.

If you have any additional questions, PM me. I hope this helps all the people like me that bought their X3 without the factory hitch, but wanted to retrofit it.

[dinan5m3]

Thanks for DYI write up, detailed.

I may go this retrofit route soon with OEM parts and finish. Not regretting on $550 option i could have had from the factory.

Originally Posted by ktmsmr12

I was told there are no factory hitches in the USA right now.

Can you elaborate on above comment?

I would probably have the dealer do this retrofit, if possible, though i don't know what that means to the mfg warranty.

Also, trying to find this information, not easy to locate. Any idea what the weight difference with and without?

Thanks much.

[supersebbo]

Awesome - thanks so much. This is detailed enough that I might try it