Curt S019 hitch - similiar to OEM

[X5chemist]

A hitch post generated some interest, so I’ll start a new one.

A BMW shop pulled this hitch off an X. The part number seems to be S019. The seller saw rear bumper scratches on mine. He remembered the X5 was also a titanium color. He offered a rear bumper for free. After looking at it, the one he had was in worse shape. Two harnesses were provided. One is a U-Haul dual version. One harness end is a four prong connection. It's more of an adapter. The other harness has a booster signal module. It connects directly to battery and ground. It's a four prong connector.

The hitch has top mount supports too. The brackets are held in place exactly where they should mount. Bolts were also included. I’ll probably go down to a bolt shop for upgrades. Mostly for locking nuts.

We opened the hood and looked it over. Two items things stuck out. First, a high mileage fuel pump. Second, an old valve cover. The second exhaust shield showed signs of oil residue. I did tighten up the bolts during a coolant system refresh. A new gasket is ready for installation once it’s warmer. The shop recommended only two pumps, VDO or OEM (Delphi?).

A previous S019 post is here.

Post about installing a rear hitch.

What did you do for your E53 today post reference.

I don't feel like butchering wires. I'll look for an OEM module and harness. What does a module actually do? Does it do transmission control? Braking?

[andrewwynn]

My understanding is that with the trailer module, the car uses different programming for DSC.

[Bdc101]

The module sends the turn signals and the brake signals to the trailer correctly. It also supplies the trailer with a +12v power wire to charge the battery. That's pretty much all it does. If you splice the brake and turn signals off of the actual brake and turn signal light wires, you will get alarms on your dash. I don't know if it affects the DSC at all, it certainly could. (Mine didn't require coding in my 2003, by the way. It was plug and play.)


The trailer module just plugs into a connector in the trunk, and then there is a bundle of wires that plugs into the module on one end and has the 7-pin trailer connector on the other. You just have to fish it through the trunk and bumper. It was pretty easy to install. I found an ebay seller making replacement wire bundles a couple years ago, since the OEM one is unavailable, but I don't know if he is still making them.

[Bdc101]

Also note: There is no trailer braking function offered from the factory for E53s, period. You have to buy an aftermarket brake controller (from Prodigy, Tekonsha, etc) and install it. There is no wire for it provided in any harness. You have to bring a wire to power the brake controller, and then run a wire from the brake controller to the 7-pin trailer connector. There is a spot for the wire but no wire on the connector.

[nahvkolaj]

The module affects the DSC to allegedly control trailer sway. It also disables rear PDC. As others said it’s plug-and-play.

I got my whole factory hitch setup from an LKQ yard for about $200. Well worth the drive and effort pulling it.

[Effduration]

I think the trailer module changes auto trans shift points....in particular higher RPMs at low speeds..

[X5chemist]

Another wiring plug was attached. The project is on hold until warmer weather is back. Or I have garage room. Plus, obtaining an OEM module with wiring will be available soon. For now, I need to get my '83C10 to pass inspection before the end of Jan!

Harnesses are available if anyone wants them. I can mail them for shipping costs. A small USPS box is cheap to mail.

[X5chemist]

Thanks to Effduration, an OEM module and harness have been acquired. The project is slowly moving along. All the parts to install it are ready. All I need is nice weather.

[Bdc101]

Nice!! I am really glad I upgraded to the OEM module. It was plug-and-play at least for my 2003, and it reduces the number of things I have to worry about when towing... already have plenty of things to be worried about!

[X5chemist]

July has been great this year. No 100 degree days. Lots of rain! I had time to polish up the mirror covers. Clay bar and wax made them look nice. I had more free time so I started looking at hitch mounting. About the only thing missing to an OEM hitch are impact bars. The "butterfly" pieces are there. Impact bar holes are plugged up.

Has anyone modified the cover to fit after a hitch installation? The cover would only leave the square sticking out. I bought new bolts. Put them in a safe place, now I can't find them.
The connector harness is ready. I'll have to dig for the controller wiring.

I assume the current crossbar has to come off. Plus, the bumper inner plate has to be trimmed. I don't have instructions so I'll have to go slow.

Is the two prong connector for a sub? Mine does not have an amp or DSP. Wish I could add an amp easily. I have rear woofers on order. The right rear one is out.