Ford 2003 Mustang Workshop Manual page 4061

Is the voltage less than 1.0 volt?
L5 CHECK FOR AN INTERMITTENT FAULT
Refer to the continuous DTCs recorded during Step L1.
Was the continuous DTC retrieved during Step L1 an
intermittent fault?
L6 CHECK FOR ADDITIONAL DTCs
Refer to the continuous DTCs recorded during Step L1.
Were any continuous DTCs retrieved during Step L1?
Pinpoint Test M: DTC B1891 — Air Bag Tone Warning Indicator Circuit Shorted to Battery or
Ignition
Normal Operation
The restraints control module (RCM) monitors its connection to the generic electronic module (GEM) at
pin 10. This connection is used to signal a chime if the air bag indicator is inoperative and another SRS
fault exists. If the RCM detects a short to battery or ignition on the connection to the GEM, it will store
a diagnostic trouble code (DTC) B1891 in memory.
Possible Causes
Yes
CHECK for causes
of intermittent
short to ground or
open on circuit
1083 (LB/BK).
Attempt to recreate
the hard fault by
flexing the wire
harness and
cycling the ignition
key frequently.
REPAIR any
intermittent
concerns found.
GO to L6 .
No
GO to L6 .
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
section for pinpoint
test direction.
No
RECONNECT the
system.
REACTIVATE the
system. PROVE
OUT the system.
REFER to Air Bag
Supplemental
Restraint System
(SRS) in this
section. CLEAR all
DTCs.