Restraints Control Module (RCM)

WARNING: This page is about a different car, the 2009 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.

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 is mounted on the center tunnel under the instrument panel. The RCM:

deploys the air bags in the event of a deployable impact.
activates the safety belt retractor pretensioners to remove slack from the safety belt webbing.
monitors the supplemental restraint system (SRS) for faults.
illuminates the air bag warning indicator if a fault is detected.
illuminates the PAD indicator when conditions warrant illumination.
flashes the air bag warning indicator to indicate the lamp fault code (LFC) detected.
communicates through the data link connector (DLC) the current or historical DTCs.
will active the chime, located in the instrument cluster (IC) module, if an air bag warning indicator fault is present and another SRS fault exists.
records deployable and non-deployable impact data.

The RCM monitors the SRS for possible faults. If a fault is detected while the ignition switch is in the RUN position, the RCM will illuminate the air bag warning indicator located in the IC module.

When the ignition is cycled (turned off and then on), the air bag warning indicator will remain lit for 6 seconds and then go out. If an SRS fault exists, the air bag warning indicator will then flash the 2-digit LFC associated with that fault. The air bag warning indicator will flash the LFC 5 times, then remain illuminated for the rest of the key cycle. The RCM will communicate current and historical DTCs through the DLC using a scan tool. If the air bag warning indicator does not function, and the RCM detects a fault condition, the RCM will signal 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.

LFCs are prioritized. If 2 or more faults occur at the same time, the fault having the highest priority will be displayed first. After that fault has been corrected, the next highest priority fault will be displayed.

The RCM includes a backup power supply. This feature provides sufficient power to deploy the front air bags, seat side air bags and the safety belt retractor pretensioners in the event that the ignition circuit is damaged in a collision before the air bags are deployed. The backup power supply will deplete its stored energy reserve in approximately one minute after the power and/or ground is removed from the RCM.