2003 BMW 325

THE CENTRAL LOCKING SYSTEM INTERMITTENTLY FAILS TO OPERATE; PROBLEM IS INFLUENCED BY TEMPERATURE EXTREMES (HOT AND COLD); SYMPTOMS VARY FROM REQUIRING THE DRIVER TO LOCK AND UNLOCK THE VEHICLE SEVERAL TIMES BEFORE THE DOORS WILL UNLOCK TO A COMPLETE FAILURE OF ALL DOORS TO UNLOCK. WHEN THE PROBLEM MANIFESTS ITSELF, THE CENTRAL ELECTRIC DOOR LOCK BUTTON (MOUNTED IN THE CENTER CONSOLE BESIDE THE HAZARD LIGHT SWITCH) IS INOPERABLE. BMW CRASH SAFETY FEATURES INCLUDE MECHANICAL DISCONNECT OF DOOR LATCHES WHEN LOCKED; WHEN THIS PARTICULAR PROBLEM MANIFESTS, SOMETIMES THE PASSENGER SIDE DOORS WILL REMAIN MECHANICALLY DISCONNECTED, MEANING THAT THE DOORS CANNOT BE OPENED AT ALL. IN A WORST CASE SCENARIO, IF THE DRIVER'S SIDE OF THE VEHICLE UNUSABLE FOR ESCAPE DUE TO DAMAGE OR BEING BLOCKED, THE ONLY WAY TO ESCAPE FROM THE VEHICLE IS BY SMASHING WINDOWS. BMWS ARE NOT EQUIPPED WITH A GLASS BREAK DEVICE. THE PROBLEM SEEMS TO BE A BODY MODULE CALLED THE GM5, WHICH IS MOUNTED ABOVE/IN FRONT OF THE GLOVE BOX; ALL LOCK POWER CIRCUITS RUN THROUGH THIS MODULE; THE PROBLEM SEEMS TO BE A VOLTAGE DROP IN THE MODULE, RESULTING IN INSUFFICIENT VOLTAGE TO THE LOCK MECHANISMS, AS YOU CAN HEAR THE LOCKS ATTEMPTING TO CYCLE WHEN AND CAN SEE THE LOCK BUTTONS MOVING WHEN THE KEY FOB IS USED IN AN ATTEMPT TO UNLOCK THE DOORS. A GOOGLE SEARCH OF THE TERMS "BMW","DOORS WON'T UNLOCK" GETS AT LEAST 10 PAGES OF RESULTS ON THE ISSUE, INCLUDING SEVERAL THAT IDENTIFY THE GM5 MODULE AS THE CAUSE OF THE PROBLEM AND WAYS TO FIX IT. REPAIR REQUIRES A NEW GM5 MODULE THAT NEEDS TO BE PROGRAMMED PRIOR TO INSTALL. *TR