need help with RDC retrofit

[TerminatorX5]

Hello.

I have had a project on my plate for a few years but unfortunately, with moves from country to country, I was not able to concentrate my efforts on the actual installation. I managed, however, to get the parts needed for the install.

The retrofit I am talking about is the one that is using the RF senders from each rim and receiving antennae in the wheel wells.

I would like to ask any member on this board, who has the system already fitted (from factory, or retrofitted to factory specs), if they could either take photos or describe in detail the mounting locations for the antennae inside the wheel wells. I have taken the wheels off, removed the plastic shrouds, and still was not able to see if there were any locations where I could install the antenna holders. It could be that I need to drill holes for the holders but for some reason I suspect that the sheet metal or the other metal parts would have either actual mounting holes or pre-punched locations identified, even if the car never had the option installed.

None of the searches that I have done show those locations - I even ended up with my own parts lists (from my old posts) quoted on some Greek beemer page... lol..

If the project is a go, i will post the DIY along with the parts list.

Thank you folks!!!

[Gregory891]

Saw your (older) post and wondered if you did this, as I'm considering this on my 2002 X5 3.0 d (I live in Switzerland).

From what I can see, it's fairly easy - assuming you have the RDC button near your shifter.

Install module in the fusebox area.
Install antenna's in the wheel housings (TIS shop manual shows removal for front & rear, I think the front one goes on the left front housing).
Install the sensors / valves in your tires.
Initialize (there is a small video on Youtube from a fellow in AUS).

Did you finish your install?

I've added front & rear mud flaps (easy), PDC (not too complicated) and the front seat first aid kit & fire extinguisher.

[SlickGT1]

So what's the point or rdc anyway. Is this like TPMS.

[TerminatorX5]

i did not go forward with it, as i could not find the factory mounting points in the wheel wells - i pulled the covers, and for the sake of my life i could not figure where the factory brackets would go... meanwhile the life got in the way, and i left the project behind, even though, it is absolutely doable:

the RDC module goes into the glove compartment area, the bracket to hold it is already there, then you would need the appropriate A169 module, the one that has the Hill Descent, the seat heaters, and the RDC button - that one is fully occupied, the RDC button is the last one on the right (the last one is the right seat heater, but there is a single slot space between the RDC and the seat heater).

I have connected the A85 module and the A169 module, wired them up and the iBus has recognised the presence of the new module... I just did not run the antennae wires...

The principal difference between the TPMS and the RDC is tha fact that he RDC is measuring the absolute value of the internalpressure and reports it through the system, while the TPMS is measuring the rotational speed of individual wheels and compares them to the other ones - and reports the 10% in the difference... As a result, the RDC will report gradual loss of pressure in all 4 tires as a reference point is a fixed value (during the reset process), and the TPMS will not report the even loss of pressure in all 4 tires as the reference point is within thse 4 tires... Other than that - the RDC is more complex as it adds more hardware, and the TPMS is simpler, as it is using the TPMS module in addition to ABS system

36-14-6-751-371 the RDC module A85 - 1
36-11-8-378-753 the receiving antennas - 4
36-11-6-751-503 the front antenna holders - 2
36-11-6-751-504 the rear antenna holders - 2
36-23-6-779-490 the tire monitors with valves - 4
61-31-8-373-740 the module A169 with RDC button - 1
61-13-8-373-650 32-pin connector for the RDC module
61-13-8-373-648 cover cap for the connector for RDC module
61-13-8-365-340 2-pin connector for antennas - 4
61-13-0-006-665 bushing contact, same as Digi-key A28327-ND
61-13-8-366-245 rubber grommets
61-13-1-387-144 ground connector
61-12-1-387-146 ground connector

here is the pinout for module A85

1 pin 12 on X332 for A1 - general module glove compartment
2
3 pin 18 on A169 - the button central console
4
5 pin 1 on B43 - fr/left antenna front left
6 shielding front left
7 pin 1 on B47 - fr/right antenna front right
8 pin 1 on B45 - rear/left antenna rear left
9 shielding rear left
10 pin 1 on B44 - rear/right antenna rear right
11
12
13
14 pin 4 on A169 - the button central console
15 pin 24 on X10460 glove compartment
16 to ground on X596 glove compartment
17 pin 4 on X253 for A1 - general module glove compartment
18
19
20
21 pin 2 on B43 - fr/left antenna front left
22 shielding front right
23 pin 2 on B47 - fr/right antenna front right
24 pin 2 on B45 - rear left antenna rear left
25 shieldingrear right
26 pin 2 on B44 - rear/right antenna rear right
27
28
29
30
31 pin 15 on X10461 glove compartment
32

[SlickGT1]

Wow. Yea no that looks intense to retrofit. TPMS and the fact that I check my pressure once a week is just fine. Lol.

[Gregory891]

For the other fellow asking what & why,

RDC = ReifenDruck Control in German (in English - Tire Pressure Monitor, i.e. TPM). BMW used this system on the early E53 which uses valve sensors (inside the rim) which send a signal to antennae (one in front wheel well, one in a rear wheel well) which then talks to the brain (in the glove box). It's a direct monitoring system of the tire pressure.

You have a warning button in the little panel that also includes the buttons for heated seats, hill descent control, PDC, etc.

They then went to the RPA (Reifen Panne Anziege in German) or FTM (English for Flat Tire Monitor as of 03 or 04/2004 which used the ABS system to check relative wheel rotation to determine a low tire (incorrect diameter relative to others).

They THEN returned to the orignal style system later (2010 to presen).

My questions are for early E53 (mine is a Euro 2002 3.0 d) that didn't have them due to trim / option level or where (US cars) this wasn't yet legally required (2008 model year cars in the US, Europe is Nov 2012 build date with Nov 2014 sale date).

Bottom line - if you retrofit, you need to install the system for the year of your car. It's not vital, and frequent use of a tire pressure gauge is cost effective and works BUT if I hear of someone who's done it on an early E53 - I'd learn and perhaps do the same.

Sensor valves are easy, adding the control module in the glovebox is simple, no coding required on the early cars - the trick is to figure out where to install the signal antennae and find the wiring harness to plug into the antennae.

[TerminatorX5]

Gregory, slight correction - they used 4 antennae and 4 transmitters for each wheel, and also one for the spare tire, which was monitored by the rear right antenna, so the stem valve on the spare tire had to be turned to the right of the car. the system was used on the E38, some E39 models...
retrofit consisted of running individual shielded cables to the glove compartment, which could be labor intensive...

not long ago i have learned that if the car was equipped with certain set of options, the other options that were not fitted at the factory were pre-wied, like heated rear seats were not installed but were pre-wired...

if the car had factory xenons, supposedly the RDC was prewired too... my car has the factory Xenons, but i never had a chance to check for the prewiring of the RDC...

i have an exact list of those options that let you retrofit things, as they are prewired - somewhere on this forum i have answered a guy who was going to retrofit the rear heatedseats, and his car was pre-wired indeed...

[Gregory891]

Thanks for the clarification, this makes more sense as you'd want to monitor all four wheels. The BMW ETK (electronic parts catalog) specifies four antennae per vehicle - hence confirmation.

I agree, if the car is pre-wired, then it's not as much hassle. Case in point, PDC (park distance control). My car is an Aug 2002 production 3.0 d (Euro X5) with Xenon. The car was pre-wired for PDC (some early X5's are not), the harness for the front sensors was under the hood. With the factory retrofit kit, an easy projet. Plug and play for the sensors (front), string the rear harness and run through the new grommet and into the car harness. Add rear sensors, plug in the control module then add the beeper and the new control panel and BINGO, you have PDC.

I need to poke around my car in warmer weather to see if I have the harness / connectors for the antennae. Then I can see if I "need" this as a project

[TerminatorX5]

Greg, here is the info on the car's main harnesses - all E53 are prewired with Level 1, it is a "plain Jane" model. then, once you have one option from Level 2, all options in Level 2 are pre-wired...
If you have one option from Level 3 - all options in Level 3 AND Level 2 are pre-wired...

So, if you have the Level 5 - youare prewired for all the lower level options, even if they are not installed...

this is only confirmed so far with heated seats and with your own statement about the PDC.

Level 2
S235 - trailer hitch
S502 - SRA (whatever it is)
S508 - PDC
S609 - Nav
S624 through S629 - telephone/radio

Level 3
S248 - steering wheel heater
S261 - rear airbags (interesting, I wonder if this is retrofittable)
S265 - RDC, tire pressure
S461 - backrest heating system in the rear
S496 - seat heating system in the rear
S533 - rear air conditioner
S536 - auxialliary heating system

Level 4
S220 - single axle level control

Level 5
S522 - xenon lights

[Gregory891]

Interesting, I'll have to check under my seat to see if there is wiring for rear seat heating (not a project) vs. my installed Xenon headlights & headlamp washing.

In Europe, if you have Xenon lights the car MUST also have headlamp washing (SRA in BMW speak, i.e Scheinwerferreiningungsanlage) and either headlamp height adjustment OR rear suspension leveling (to keep them aimed).

SRA is headlamp washing.

I'll put the tire monitor on my "list" but it's lower down the list after I add the sport rear bar & Bilsteins (in my garage now), as well as the multifunction steering wheel (to have cruise and other functiosn) - I'll get this tomorrow.