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Body Control Module (BCM) - Programming - General Information

The service BCMs EEPROM chip must be programmed with the proper RPO configurations by using a scan tool. The EEPROM stores information regarding the vehicle options and point of sale. If the BCM is not properly configured with the correct RPO codes, the BCM will set default values for some Systems, which could cause malfunctions in other systems. When the BCM is replaced, the BCM must be programed to identify the following information:
^ Country of Sale (US, Canada, Europe, Japan, etc.)
^ Real Time Damping (RTD)
^ Memory Options
^ Front Fog Lamps
^ HVAC (C60-Manual, CJ2-Automatic)
^ Active Handling
^ Auto Headlamp Control
^ Power Tilt/Telescope Column

The BCM sends password information to the PCM on the serial data line to enable fuel for Content Theft Deterrent (CTD) functions, therefore, the PCM must also be programmed to accept the new password sent by the BCM. The BCM programming procedure will enable the learn password mode for both the BCM and PCM. This mode allows the PCM to learn the new password sent by the BCM whenever the BCM or PCM is replaced. If the BCM and PCM is not properly programmed together, the vehicle will exhibit a no start condition and the PCM will store a DTC P1631.

When an ignition key or the BCM is replaced, the BCM must be programmed to accept the resistance value of the new or existing vehicle keys in order to allow PASS-key operation. When the BCM is replaced, the service replacement BCM is programmed to accept the first PASS-key resistance value detected. If the BCM is unable to detect a valid PASS-Key resistance value, the BCM will never end the programming sequence and a DTC B2735 will set. The BCM can also be programmed to accept a new PASS-Key code by completing the following BCM/PASS-key programming procedure:

IMPORTANT: Before proceeding with this programming procedure, check for proper communications between the BCM and PCM. If communications cannot be established, refer to the appropriate Diagnostic System Check for the system unable to communicate.

Maintain the battery voltage while the PCM is in the Auto Learn Procedure. Follow this procedure exactly as indicated or you will have to repeat the procedure from the beginning.