BMW X5 right rear door keyless entry function failure

A mileage of about 55,000 km of the 2008 BMW X5. Customers reflect : the right rear car door keyless entry function loss .
After receiving the car : first Transponder Key confirm Symptom , right rear car door keyless entry function total loss , but no other door keyless entry function properly.
Normal BMW X5 car keyless entry function is the key in the door 2m distance range , simply press the door handle , door handle sensors will signal the start to pass through CAN-BUS system control unit (CA) and convenient entry and start system ( CAS), CAS activate dormant and CA. WAKE-UP CA through a dedicated line to activate a number of merit-based module FBD antenna. CA to be activated while the vehicle 's key identification issued 125 kHz radio signals required by CAN-BUS car door handle inside antenna. After the confirmation key for decoding the identification of the vehicle outside the vehicle belongs to the wireless signal received , CA sent 868 kHz radio frequency signal to the key identification number in the FBD antenna diversity module , FBD antenna the received key identification signal passed a number of merit-based radio signal receiver modules DIV authenticate and OBDII Code Reader verify the results sent to CAS, after successful authentication , CAS unlock authorized to issue and notify the junction box control unit executes instructions to unlock the door unlocked.
ISID fault detector connected vehicle test results without any associated fault record . According to the control theory, analysis of the causes of the failure are as follows : an antenna inside the right rear door handle damaged ; line fault car door handles to the CA or the CAS ; door handles identification device failure.
After replacing the right rear door handles antenna test , the fault persists ; replace the right rear door handles test, the fault persists . So access to relevant circuit, ready to measure the door handle to the CA or CAS lines. When ready to connect the adapter to measure signal line before checking the right rear door handles connectors, MINI TAG KEY TOOL accidentally discovered the connector into the line of three , while on the connector only two terminals , refer to the relevant circuit diagram found on the connector should have 3 lines. The three signal line connector on the rear Skip connectors, door handles direct connection test , the right rear door keyless entry function returned to normal .
Troubleshooting: After replacing the right rear door handles connector commissioning , troubleshooting.