You may find a lot of articles and forum posts refer to the T5 BCM, but what exactly is a BCM and why does it matter to the retrofits you can do on your T5.
So, What is a BCM? BCM stands for Body Control Module and it is the module that controls the main functions within the vehicle, such as headlights, foglights, central locking etc. It monitors and controls these circuits directly, via relays or via communication with the specific module for that function. The communication is done via the CAN bus network within the vehicle.
Where is the BCM located on a T5?
The BCM is located on the off side of the vehicle, behind the dashboard. To get access to it, you will need to remove the lower dash panel located beneath the steering wheel. Rather than create my own guide on how to remove it and get access, I’ll link to this guide as it has great pictures and steps on how to find your BCM .
Why it matters which BCM you have
There are 5 different types of BCM which could be found on your T5, however, not all of them support the same features. For example, there are only 3 which support Cruise Control and only 2 which support Bi-Xenon headlights.
The part number of the BCM will be in the format of 7H0 937 0xx where xx will be either 86, 87, 88, 89 or 90. Below you will find the features that each model support.
7H0 937 086
Supports Multifunction steering wheel (MFSW), Remote central locking, Anti-theft system, Outside mirror heating and seat heating.
7H0 937 087
Supports the same features as the 7H0 937 086 model but with the addition of Cruise Control and Anti-theft system LIN-databus, which is used for the Alarm horn.
7H0 937 088
Supports the same features as the 7H0 937 087 but with the addition of Start/Stop.
7H0 937 089
Supports the same features as the 7H0 937 088 but with the addition of certain lighting functions (such as LED DRL, Bi-xenon, etc.)
7H0 937 090
Supports the same features as 7H0 937 089.
So what does all this mean? Well depending on what functionality you are wanting to retrofit, you need to ensure that you have the correct BCM. The most common retrofit people want to perform is to fit cruise control, so if you have the 7H0 937 086 BCM and you want cruise control, then you will need to upgrade to a BCM which has a part number of 7H0 937 087 or higher. All BCM’s support the features of the part number with the lower number, i.e. 087 will support all the features that 086 will have.
Part number suffix
The part numbers can also be suffixed with a character and it’s important to make sure you have the correct one for your vehicle. Why? well depending on the model of the BCM, it could be using a different frequency for the remote central locking, therefore you won’t be able to recode your remote fob to work with the new BCM. You can see which frequency your vehicle uses by checking on the key itself, open up the key blade which should expose some writing, within that you should see the either 434 MHz or 315 Mhz. Part numbers suffixed with the letter B, D, F, H, K, M, P, R, T all work on the 434 MHz frequency and part numbers suffixed with the letter A, C, E, G, J, L, N all work on the 315 MHz frequency
I hope this post helps someone out and if you have any questions, drop a comment below and i’ll try and help you out.