the trailer brain is an extension of the Light Module - it controls the rear lights, the PDC (cuts off rear PDC when trailer is hooked up)... I do not think it does braking on the US model, and not so sure about the EU/worldwide models...

Trailer Module (AHM)

Absatz
Trailer module (AHM)

The trailer module is a peripheral module of the light module and only operates in conjunction with this module. It is fitted together with the trailer towing hitch special option.
It is necessary for disconnecting the load power circuit of the trailer from the current circuits of the towing vehicle thus enabling separate monitoring of the vehicle lamps and trailer power circuits.
Diagnosis takes place via the light module.
Turn signal indicator, side light, brake light
The trailer module receives the switch-on data for the turn signal indicator, side lights and brake lights via the lines connected to the rear lamps of the towing vehicle.
Rear fog light, reversing light, communication
The rear fog light and reversing light are not switched directly by the lamps of the towing vehicle as the corresponding lamps on the car must be extinguished with the trailer hitched up.
The trailer module communicates with the light module via a data link between the light module and trailer module.
The rear fog light and reversing light are controlled via this data link.
The trailer module transfers error messages to the light module with regard to faults in the trailer power circuits.
The rear fog light is switched off in the event of an interruption in communication between the light module and trailer module for more than two seconds.
Communication is re-attempted every time terminal 15 is switched on.
If communication between the light module and trailer module was already set up once and is now interrupted, the corresponding fault code is entered in the fault code memory of the light module.

the 54-pin plug is definitely one for the BT or Telematics unit... the BT is using black/purple FAKRA plug, but i am not sure about the blue/black FAKRA - it could be the telematics/SOS antenna plug, or it could be a loop-back to the central console - there is a spot for an antenna in the armrest - i have an old post somewhere where i have a picture of that antenna... i need to search for that post... long time ago... :)

the flat 3-pin plug is the power and i-bus for the CD-changer (used by many to connect aftermarket music systems), and the 6-pin is the sound part of the CD-changer pre-wiring...

The blue plug with something connected there - that is the unknown plug... i suspect that it takes care of the SES module, but i am not so sure... how many pins is that plug?

Im not exactally sure, but its alot, I will count this morning to get exact. I was under the impression that this unit had the phone already, as per the build sheet, but are you thinking that is incorrect? I am wondering what its going to take to put a factory BT in.

I would say at this point that my truck probably has the highest wiring harness and it is not prepped for navigation, would that be a safe bet? If it warms up today Im going to pop off the top of the spoiler to run my satellite radio antenna and see what else is in there.

Although I dont like the factory Nav peices in the E53's I am not willing to gut this system as I did in my E39 so installing the factory stuff seems appealing, we take this car on most long trips so having navigation is helpful and I really dont want to hang anything from the windshield, or on the dash, etc. I am curious if I can install the monitor, without the Nav computer and install an older alpine remote controled Nav system to be used with the factory monitor. I have heard you can install the TV tuner without the Nav system to get the monitor to fire up. This would be great as I have the Alpine Active view rear camera system that I would like to have work through the system as well as the BMW PDC I am working on finding the parts for.

As far as the Hitch, I now understand what the module is doing and probably needs to be installed, I see that ECS tuning has the module and wiring available for a decent price as I have already sourced the hitch somewhere else, I will probably go that route, Im curious tho, what can these things pull? Can I pull my e39 on my 20' flatbed? Its not a big deal as I can use my 1 ton dodge, but it would be convienent if the X would pull some as well.

Is there anything else I need to pull apart and check? I did find a 2 pin plug located next to the subs up high behind the panel....Is this where the PDC speaker plugs in...you made mention of a speaker for the PDC up front, do you know the location where that is supposed to go? I was under the impression that it used the car speakers for that function, but am I wrong? Also, the button to shut the front sensors down, it should be pre wired at the console as well correct?

you should have the highest level if you have the xenon lights - according to the theory that we are trying to prove...


factory TV module will power up and operate the front monitor, and will have its own menu generated, like "onboard comp", "aux ventilation", "DSP" and whatnot... you will have "television" but not the "GPS", and the graphics will look a bit different... The TV module has its own AV input/output (mono audio) and a dedicated rear camera input.


the X5 is rated at 6000 lbs nominal with proper installation of the hitch but i think smaller engines (3.0) are at 5000 lbs - there are many posts on the towing... I saw a post where a member was towing a huge boat, on the picture it looked 3 times the size of the X...

the front speaker is in the driver's side footwell...

Yes, have xenon lights, rear seat heaters..... Pretty much everything that I can think of less PDC and Nav.

Anything for Tire monitoring?

In your opinion, would it be less expensive to buy the nav harness from bimmernav and source the rest of the parts or just spend the 2800 on the complete kit that they offer? Is there modules to allow me to install atleast one camera, as well as other inputs, ie dvd to be shown on the monitor? I would assume that Dice will work the same.

if you are going with the factory monitor, you will need something to run the video - either the nav comp, or the tv module... the tv module will give you also the av input/ouput and the rear camera... if you go with the nav comp, you need to have something for the video input, and there are two factory options, the tv module (agains) and a specila module just for the cameras (i have not seen that module installed ever, other than the catalogs)... you can try to source the components separately, the harness is the one sigle piece that is hardest to come by (that is why i was hoping that the car is prewired for it)...

in the preface E53 the tire monitoring was done by RDC and the facelifet ones is TPMS (ABS based system). the RDC is most labor intensive, it calls for the unit to be put behind the glove compartment, 4 antennas fitted in the wheelwells, senders fitted into the rims... however, very precise, as it gives you warning when there is a 5% drop in absolute pressure in the tire (while system knows which tire it is, there is not indication to tell you which one it is... go figure)... the newer system is using the ratational speed of the wheels to determine if one tire is spinning at different speed than the other three - not as reliable, if all four tires lost the pressure, it will not report problem, the difference must within 20% of pressure... but easier to install, only a brain in the glove compartment and correct module A169 (the seat heater, hill descent button..)

Ok, im not quite sure I understand. If I go with oem monitor and nav computer, I will have an imput for camera? is there only one input? I would like to have DVD video if possible as well.

Have you ever seen the RDC monitor system ever installed? Do they have a retrofit?

if you go with OE monitor and OE nav - NO video, NO AV input...

if you go with OE monitor, OE nav and OE TV tuner - video and AV input

if you go with OE monitor and OE TV tuner - video and AV input

the OE tuner is the one giving you the rear camera and the AV...

nav computer - will not do that...

I have all the parts needed for the RDC installation, the reason i did not go with it, as i could not find mounting spots in the wheel wells for the antennas, even though i had the pictures of the factory RDC antenna locations... if you need the parts list for the RDC, let me know, i will post them (i have a thread for it, about 3-5 years old, somewhere on this forum...)

Yeah, I would like to see the RDC info.

Dont you have a backup camera system? I was assuming you had the OEM monitor, so you must have the TV tuner as well?

yeah, i have the back up camera with the OE monitor and OE TV tuner...

I will get the RDC info later on...