Audi Repair: AUDI A4 ALARM AND CENTRAL LOCKING FAULT, electronic control module, rear doors

Question
I HAVE A 2001 A4, IT SUDDENLY STOPPED REMOTE LOCKING ALSO ALONG WITH THIS FAULT THE REAR DOORS WILL NOT LOCK, THE DOOR OPEN DISPLAY ON THE DASHBOARD DOES NOT RECOGNISE THE REAR DOORS TO BE OPEN. ON THIS DISPLAY IT ALSO SHOWS THE OPPOSITE DOOR OPEN TO WHAT IS ACTUALLY OPEN. COURTESEY LIGHTS DO NOT OPERATE WHEN REAR DOORS OPENED. I HAVE CHECKED KEY FOB BATTERY, FUSES, ELECTRONIC CONTROL MODULE FOR WATER, DISCONNECTED BATTERY, CONNECTIONS TO REAR DOORS. HAVE YOU ANY THOUGHTS?

Answer
Perhaps the rear door contact switches themselves are dirty or are malfunctioning?  If the courtesy light is non fucntional, the central locking module itself may have developed a problem; difficult to tell I would do some tests with an Ohmmeter to see if all the contacts are functional; you will need to get a wiring diagram.  Let me know what you find,  Jan