Body Control Module: Description

BCM's Electronically Erasable Programmable Only Memory (EEPROM) chip must be programmed with proper RPO configurations. EEPROM stores information about vehicle options and point of sale. When BCM is replaced, new BCM must be programmed to identify the following information:

Real Time Damping (RTD).
Memory options.
Daytime Running Lights (DRL).
Front foglights.
Tire Pressure Monitor (TPM).
HVAC (manual or automatic).
Country of sale (US, Canada, Europe, etc.).

If BCM is not properly configured, BCM will set default values for some systems, which may cause faults in other systems.

Since BCM sends a password to PCM, PCM must also be programmed to accept the new password. BCM programming procedure will enable learn password mode for BCM and PCM (this mode allows PCM to learn new password sent by BCM whenever BCM or PCM is replaced). If BCM is not properly programmed, vehicle will exhibit a no-crank condition.

When BCM is replaced, new BCM must be programmed to accept resistance value of existing vehicle keys so that it will allow PASS-Key(R) operation. The new BCM is programmed to accept the first PASS-Key(R) resistance value detected. If BCM is unable to detect a valid PASS-Key(R) resistance value, BCM will not end programming sequence and DTC 2735 will set.

NOTE: Maintain proper battery voltage during programming procedure and perform steps as specified, or programming procedure will have to be repeated.

NOTE: When programming procedure is performed, DTC P1630 will set (this is normal). When DTC P1630 sets, turn ignition off for 30 seconds, then turn ignition on. DTC P1630 should clear. If DTC P1630 does not clear, see TESTS W/CODES article in ENGINE PERFORMANCE section.