Restraints Control Module (RCM)

WARNING: This page is about a different car, the 2008 Ford RV Cutaway, 2008 Ford Econoline, 2008 Ford E450 Super Duty, and 2008 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.

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.

NOTE: Prior to removal of the restraints control module (RCM), 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. Refer to MODULE CONFIGURATION article.

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 DTCs will result.

The RCM carries out the following functions:

Deploys the air bag(s) 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 (IC) module to illuminate the air bag warning indicator if a fault is detected
Communicates through the data link connector (DLC) the current and/or historical DTCs

The RCM monitors the SRS for possible faults. If a fault is detected, the RCM will request the IC module to illuminate the air bag warning indicator. When the ignition is turned OFF and then ON, the IC module will prove out the air bag warning indicator by lighting for 6 seconds. If no faults are detected by the RCM the IC module will turn the air bag warning indicator off and it will remain off. If the RCM detects a fault it will send a message to the IC module to turn the air bag warning indicator on and it will remain on for the rest of the key cycle. If the RCM requests illumination of the air bag warning indicator and the air bag warning indicator does not function, the IC 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. The backup power supply will deploy the SRS components in the event that the ignition circuit is lost or damaged during impact. The backup power supply will deplete its stored energy approximately one minute after power and/or ground has been removed from the RCM. The backup power supply will deplete its stored energy approximately one minute after the battery ground cable is disconnected.

The RCM will also communicate the on-demand (current) and continuous (historical) DTCs through the DLC, to the scan tool.