Ford 2003 Mustang Workshop Manual page 4015

current and historical DTCs through the DLC, using a scan tool. If the air bag indicator does not
function, and the system detects a fault condition, the RCM will signal the GEM to activate an audible
chime. The chime is a series of five sets of five tone bursts. If the chime is heard, the SRS and the air
bag indicator require repair.
LFCs are prioritized. If two or more faults occur at the same time, the fault having the highest priority
will be displayed. 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 backup power to deploy the
air bags in the event that the ignition circuit is damaged in a collision before the safing and air bag
sensors determine that deployment is required. The backup power supply will deplete its stored energy
approximately one minute after the battery ground cable is disconnected.
Electrical System
The electrical system that supports the air bag supplemental restraint system (SRS):
is powered from the battery through the ignition circuit.
provides the electrical path from the restraints control module (RCM) to the air bag modules.
provides the electrical path from the RCM to the air bag indicator.
provides the electrical path from the RCM to the data link connector (DLC).
provides the electrical path from the RCM to the generic electronic module (GEM).
Sensor
WARNING: The restraints control module (RCM) orientation is critical for proper system
operation. If a vehicle equipped with an air bag supplemental restraint system (SRS) has been
involved in a collision in which the center tunnel area has been damaged, inspect the mounting
and bracket for deformation. If damaged, the RCM must be replaced whether or not the air bags
have deployed. In addition, make sure the area of the RCM mounting is restored to its original
condition.
The SRS contains two sensors which are integral to the RCM. The RCM is mounted on the center
tunnel under the instrument panel.