Restraints Control Module (RCM)

WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Do not handle, move or change the original horizontal mounting position of the restraints control module (RCM) while the RCM is connected and the ignition switch is ON. Failure to follow this instruction may result in the accidental deployment of the safety canopy and cause serious personal injury or death.

WARNING: If a vehicle has been in a crash, inspect the restraints control module (RCM) and the impact sensor (if equipped) mounting areas for deformation. If damaged, restore the mounting areas to the original production configuration. A new RCM and sensors must be installed whether or not the air bags have deployed. Failure to follow these instructions may result in serious personal injury or death in a crash.

CAUTION: Prior to removal of the restraints control module (RCM) module, it is necessary to upload module configuration information to the scan tool. This information needs to be downloaded into the new RCM module once installed. Failure to follow these instructions may result in incorrect operation of the supplemental restraint system (SRS) and may cause system failure.

NOTE: When installing a new restraints control module (RCM), always make sure the correct RCM is being installed. If an incorrect RCM is installed, erroneous diagnostic trouble codes (DTCs) will result.

The restraints control module (RCM) carries out the following functions:

deploys the air bag(s)/safety canopies in the event of a deployable collision.
activates the safety belt buckle pretensioners to remove slack from the safety belt in the event of a deployable collision.
monitors the supplemental restraint system (SRS) for faults.
sends a message to the instrument cluster module to illuminate the air bag warning indicator if a fault is detected.
communicates through the data link connector (DLC) the current or historical diagnostic trouble codes (DTCs).

The RCM monitors the SRS for possible faults. If a fault is detected, the RCM will request illumination of the air bag warning indicator.

When the ignition is cycled (turned OFF and then ON), the instrument cluster will prove out the air bag warning indicator by lighting for 6 seconds and then off. If a current SRS fault exists, the RCM requests illumination of the air bag warning indicator and will remain illuminated for the rest of the key cycle. During that same key cycle some faults that recover, i.e. Loss of Communication with the PCM, the RCM will send a request to the instrument cluster module to turn the air bag warning indicator off IF no other fault is present. The RCM will also communicate the on-demand (current) and continuous (historical) DTCs through the DLC, to the scan tool. If the RCM requests illumination of the air bag warning indicator and the air bag warning indicator does not function, the instrument cluster module will automatically activate an audible chime. The chime is a series of 5 sets of 5 tone bursts. If the chime is heard, the SRS and the air bag warning indicator require repair.

The RCM includes a backup power supply. This feature provides sufficient backup power to deploy the SRS in the event that the ignition circuit is lost or damaged during a collision. The backup power supply will deplete its stored energy approximately one minute after the battery ground cable is disconnected.