Since there was some time over the holidays, I started retrofitting the seat heating plus the associated control unit.
This is possible on all R1200GS(A) and R1250GS(A) that have at least a BMW TFT display.
Prerequisites for this to be possible:
- TFT display
- the BCO (light base module from 05.2017) - Conversion instructions for older control unit here
- E-Net cable
- BimmerUtility
The following BMW part numbers are required for the retrofit:
| BMW part number | Description |
| 61121683927 | Wiring harness satellite control unit |
| 61128548716 | Adapter wiring harness driver seat |
| 61127688147 | Adapter wiring harness passenger seat |
| 61358405640 | Base module satellite |
| A seat with the original seat heating from e.g. BMW or Wunderlich |
The procedure here is relatively simple; you only have to adapt the 4 wires of the wiring harness to the motorcycle's wiring harness. The assignment by cable colour is quite straightforward:
| Cable colour | Function |
| Green/White | +12V |
| Brown | Minus/Ground |
| Blue | CAN-H |
| Grey | CAN-L |
You will find the same colours in the original wiring harness of the R12(0/5)0GS(A) models.
In my case I took the socket from an old wiring harness and built an adapter so that it can be unplugged again. This makes particular sense because the R1200GS and R1250GS up to 2020 have no space to the right of the ABS control unit, where this new control unit was installed at the factory from 2020. In my case, mine sits in the place of the old light control unit, next to my new SOS emergency call control unit directly behind the battery. The space worked out quite well. The new light control unit sits directly under the tank. For you the location will probably be a different one.
What is the BMW satellite control unit actually intended for:
The name satellite actually means accessory, as this control unit is responsible for a number of functions on the RT (also police) and GT models, e.g. central locking, auxiliary lights and authority functions.
In the GS(A) only the seat heating function is used.
Once everything is plugged together, it is time to code. I did this coding with BimmerUtility, as I did not want to lose my special codings.
First we extend our vehicle order by the option 518 seat heating. When saving, you can confirm all coding options if you have not coded anything special, such as sport display or position lights. In that case the conversion is already done.
If you have special codings that you do not want to lose, decline the coding and change the options by hand.
The manual codings continue in the TFT display. Here we unlock access while riding and enable a 6-level setting for the grips and the seat. To do this, select the last option in the pull-down and adjust the value manually. (visible in the white field above the pull-down in the screenshot)
we set levels 1-6 for the grips and switch the function of the seat heating button so that all control works via the TFT.
Now we are still missing the satellite control unit (called X_FSA); here we of course also set our 6 heating levels and that the messages come via the CAN bus.
Frequently asked questions (FAQ)
Required are a TFT display, a BCO base module (light) from model year 05/2017, an ENET cable and the BimmerUtility software. In addition, an original seat with seat heating and the matching satellite control unit are needed.
The satellite control unit (X_FSA) originally comes from RT/GT models, where it controls further comfort functions such as the Central locking. On the GS(A), only the seat heating function is used and coded as part of this retrofit.
Communication takes place via the in-vehicle CAN bus. After wiring, the appropriate CAN bus message options are coded in the BCO basic module and in the satellite control unit, so that 6 heating levels can subsequently be set via the TFT display.