BMW E90 E91 3-Series – Doors Will Not Unlock – 325i, 328i, 330i, 335i, etc.
Q Car Year: 2007
Car Model: 335i
All of a sudden the remote locks on my BMW will not work. The doors will not unlock using the remote button on the key. Does Otto have any idea what may be wrong?
There is a common fault that generally applies to the early E90 and E91 3-series models. This would be the sedan and wagon models produced from the model years 2006 through 2008 (323i, 325i, 325xi, 328i, 328xi, 330i, 330xi, 335i, 335xi). In this case, the electric locks will not work from either the remote key fob or the central locking button in the vehicle. This fault can affect all of the doors and the fuel door or may be limited to just the front doors or just the rear doors and fuel door. If the front is non functional, the locks will work when actuated manually via the key itself or the interior door handles. If the rear systems are inoperative, the doors and fuel door cannot be opened normally (the fuel door can be opened via the emergency release in the trunk).
The failure is typically related to a blown system fuse due to one or more of the lock actuators drawing a higher current than normal. The first step in diagnosis and repair is to access the two system fuses (see fuse location notes below) and check if either is blown. If yes, replace the blown fuse with a 20-amp fuse (original is 15-amp). Perform a lock cycle procedure as noted below to verify if one of the locks is faulty.
Models through 08/2007 production – Fuse #56 & #57 in main fuse box
Models produced from 09/2007-on – Fuse #72 & 73 in main fuse box
Lock cycle procedure:
Activate/cycle the locks 10 times in rapid succession, using the central locking button in the vehicle. Pay close attention to see if one of the lock actuators may begin to react slower or make any abnormal noise. Note that the thermal protection feature will deactivate the system after approximately 15 cycles. In this case, let the system rest to reset.
If all appears to be normal, leave the 20-amp fuse in-place. The blown fuse was likely an errant amperage draw spike. Note that the 20-amp fuse is approved and recommended by BMW.
If one or more of the locks does exhibit signs of abnormal operation, the actuator/latch assembly should be replaced. Front units must be replaced in pairs (with updated versions), while the rears can be replaced individually.
Front actuator/latch assembly (pair)
Left or Right rear actuator latch