Is your F30 locking and unlocking itself? Here's what to do
Is your car locking itself? Here’s what could be wrong
The F30 generation 3 Series was well received by the aficionados. It may have its downsides, like the change from a hydraulic steering system to an electrically-assisted one, but overall, it was and still is a better offering compared to the older E90 models. However, all the new tech it has on-board does include a lot more electronics and, as we all know, that can lead to all sorts of issues.
If you live in a wetter part of the world, there is a slight chance that after a downpour, your car might misbehave. To be more precise, it could start locking and unlocking itself. This process might not necessarily happen when stationary; there are reported cases where the car started misbehaving like this when driven on the Autobahn. But what exactly causes that?
Well, as it turns out, this is a rather common issue on both F30 3 Series models and F32 4 Series Coupe, F33 4 Series Convertible and F36 4 Series Gran Coupe. BMW even issued a recall a while back for some of these cars, but from what you can read on various forums, the problem wasn’t permanently fixed.
What happens is that the FEM (Front Electronic Module) can go faulty for various reasons. Most commonly, water seeps through in heavy rain and damages the internals, causing it to malfunction but there have been cases where the FEM stopped communicating with the car during programming or while using ISTA-P.
Luckily, you don’t have to buy a new one, the old unit can be fixed. To do this, you’ll have to physically remove the FEM from your car along with the DME and ship it along with your keys to a specialist, to have it reprogrammed or physically fixed, depending on the issue. Normally this would set you back a few hundred dollars and just a couple of days.