Ford 2003 Mustang Workshop Manual page 4031

Is the voltage between 9 and 16 volts?
A5 CHECK THE GROUND CIRCUIT 397 (BK/WH) FOR AN OPEN
Key in OFF position.
Measure the resistance between RCM C2041 pin 21, circuit 397
(BK/WH), harness side and a sheet metal ground near the RCM.
Is the resistance less than 10 ohms?
A6 CHECK CIRCUIT 608 (BK/YE) FOR A SHORT TO GROUND
Connect: RCM C2041.
Disconnect: Instrument Cluster C220a.
Measure the resistance to ground at instrument cluster C220a pin 12,
circuit 608 (BK/YE), harness side.
Is the resistance less than 10,000 ohms?
A7 CHECK FOR ADDITIONAL DTCs
Refer to the continuous DTCs recorded during Step A1.
Were any continuous DTCs retrieved during Step A1?
Yes
GO to A6 .
No
REPAIR the
circuit. GO to A7 .
Yes
REPAIR the
circuit. GO to A7 .
No
INSTALL a new
RCM. GO to A7 .
Yes
Do not clear any
DTCs until all
DTCs have been
resolved. GO to
the Restraints
Control Module
(RCM) Diagnostic
Trouble Code
(DTC) Priority
Table in this