NOTE: I cannot provide technical assistance (I don’t even have a BMW, nothing but Lexus & Toyota on my keyring). If you need more information I recommend https://www.bmwgm5.com/ where you can get diagrams, info and replacement relays.
https://www.bmwgm5.com/Door_lock_schematic.htm is a very good place to start.
As the title suggests, this vid shows you how to get the module out of the car (a fairly important step) and replace the two double relays responsible for central locking.
If you have one of the following vehicles and have a central door locking fault that affects all doors (not just one), these instructions are probably for you:-
3-series (E46 model) 1998-2005
X3 (E83 model) 2003-2010
Z4 (E85 model) 2002-2008
Z8 (E52 model)
The original relay is a Siemens or Tyco (TE) V23084-C2001-A303, which uses 255Ω (±10%) coils drawing a maximum (based on 255Ω -10%) of 60mA at 13.8V and features AgNi0.15 contacts.
Other relays in this family are:-
V23084-C2001-A403 (255Ω ±10% coil, AgSnO₂ contacts)
V23084-C2002-A303 (178Ω ±10% coil, AgNi0.15 contacts)
V23084-C2002-A403 (178Ω ±10% coil, AgSnO₂ contacts)
The C2002 types draw a maximum of 86mA at 13.8V.
AgSnO₂=Silver Tin Oxide
AgNi0.15=Silver Nickel
The relays are all driven by a pair of ULQ2003AD transistor arrays, this includes the four large front window relays which use 107Ω (±10%) coils (max. 143mA at 13.8V).
Post time: Oct-13-2017