2003 FORD MUSTANG warning

DIAGNOSIS AND TESTING
Pinpoint Tests —
Air Bag Supplemental Restraint System
(SRS)
Restraint System Diagnostic Tool Warning
WARNING: This tool is for restraint system service only. Remove from vehicle prior to
road use. Failure to remove could result in injury and possible violation of vehicle safety
standards.
Pinpoint Test Note
Do not carry out any pinpoint test unless directed by the Symptom Chart.
Pinpoint Test A: The Air Bag Warning Indicator Is Illuminated Continuously — RCM
Disconnected, Inoperative or Lost/Low Ignition Feed
Normal Operation
NOTE: During normal operation the air bag indicator will be lit continuously for 6 seconds after the
ignition switch is placed in the RUN position and after five cycles of a lamp fault code (LFC) if a fault
exists. Be sure to cycle the ignition switch and look for a 6 second indicator prove- out without LFCs.
The restraints control module (RCM) will communicate diagnostic trouble codes (DTCs) to the scan
tool through the data link connector (DLC). If the scan tool displays NO COMMUNICATION when
retrieving continuous DTCs, Go To Pinpoint Test P to troubleshoot the system.
Possible Causes SECTION 501-
20B: Supplemental Restraint System 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent Diagnostic Tool, Restraint
System
418-
F088 (105- R0012) Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool Klj . 1 ba
462003 Mustang Workshop Manual
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An air bag indicator that is illuminated continuously can be caused by one of the following:
zworn or damaged shorting bar or camming beam.
z the ignition circuit damaged.
z the RCM disconnected from the vehicle harness.
z a loss of RCM ground circuits.
z the RCM inoperative.
z circuitry.
PINPOINT TEST A: THE AIR BAG WARNING INDICATOR IS
ILLUMINATED CONTINUOUSLY — RCM DISCONNECTED,
INOPERATIVE, OR LOST/LOW IGNITION FEED Test Step Result / Action to
Take A1 CHECK FOR CONTINUOUS OR ON-
DEMAND SELF TEST DTCs z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this pinpoint
test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Were any continuous or on- demand self test DTCs retrieved? Yes
If continuous
DTCs were
retrieved, GO to
A3
. If on-
demand
DTCs were
retrieved, GO to
the Restraints
Control Module
(RCM) Diagnostic
Trouble Code
(DTC) Priority
Table in this
section for
pinpoint test
direction.
No
GO to A2 .
A2 CHECK THE RCM CONNECTION
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section.
The air bag restraint system diagnostic tools must be removed
and the air bag modules reconnected when the system is
reactivated to avoid non- deployment in a collision, resulting in
possible personal injury. NOTE: Diagnostics or repairs are not to
be performed on a seat equipped with a seat side air bag with the
seat in the vehicle. Prior to attempting to diagnose or repair a seat
concern when equipped with a seat side air bag, the seat must be
removed from the vehicle and the restraint system diagnostic tools
must be installed in the seat side air bag electrical connectors. The
restraint system diagnostic tools must be removed prior to
operating the vehicle over the road. NOTE: After diagnosing or Yes
GO to
A3 .
No
CONNECT C2041
and engage the
locking tabs. GO
to A7 . Klj . 2 ba
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Pinpoint Test B: LFC 21/DTC B1921 —
RCM Bracket Ground Resistance High
Normal Operation
WARNING: The tightening torque of the restraints control module (RCM) retaining bolts is
critical for proper air bag supplemental restraint system (SRS) operation. Refer to Restraints Control Module (RCM) in this section for correct torque values.
The restraints control module (RCM) monitors the resistance between the ground connections at its
housing and the reference ground at pin 21. If the RCM detects a resistance greater than 100 ohms, it
will store a diagnostic trouble code (DTC) B1921 in memory and flash a lamp fault code (LFC) 21 (or
higher priority code if one exists) on the air bag indicator.
Possible Causes
High resistance between the RCM housing ground and pin ground can be caused by:
zincorrect seating of the RCM retaining bolts.
z incorrect tightening torque of the RCM retaining bolts.
z high resistance on RCM logic ground circuit 397 (BK/WH).
PINPOINT TEST B: LFC 21/DTC B1921 — RCM BRACKET GROUND
RESISTANCE HIGH 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. Test Step Result / Action to Take
B1 CHECK FOR A HARD OR INTERMITTENT DTC
z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in
this pinpoint test.
z Enter the following diagnostic mode on the diagnostic tool:
On- Demand Self Test.
z Was DTC B1921 retrieved during the on- demand self Yes
This is a hard fault. The fault
condition is still present. This
fault cannot be cleared until it
is corrected and the DTC is
no longer retrieved during the
on-demand self test. GO to
B2 .
No Klj . 5 ba
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z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this pinpoint
test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC C1414 retrieved during the on- demand self test? Yes
This is a hard
fault. The fault
condition is still
present. This fault
cannot be cleared
until it is corrected
and the DTC is no
longer retrieved
during the on-
demand self test.
GO to
C2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
C5 .
C2 CHECK THE VEHICLE IDENTIFICATION PINS NO. 1 AND NO. 2
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section.
The air bag restraint system diagnostic tools must be removed
and the air bag modules reconnected when the system is
reactivated to avoid non- deployment in a collision, resulting in
possible personal injury. NOTE: Diagnostics or repairs are not to be
performed on a seat equipped with a seat side air bag with the seat in
the vehicle. Prior to attempting to diagnose or repair a seat concern
when equipped with a seat side air bag, the seat must be removed
from the vehicle and the restraint system diagnostic tools must be
installed in the seat side air bag electrical connectors. The restraint
system diagnostic tools must be removed prior to operating the
vehicle over the road. NOTE: After diagnosing or repairing an SRS,
the restraint system diagnostic tools must be removed before
operating the vehicle over the road. NOTE: After diagnosing or
repairing a seat system, the restraint system diagnostic tools must
be removed before operating the vehicle over the road. NOTE:
The SRS must be fully operational and free of faults before releasing
the vehicle to the customer. NOTE: For this vehicle application, RCM
C2041 pins 10 and 13 should be open circuited.
z Key in OFF position.
z Deactivate the system. Refer to Air Bag Supplemental Restraint System (SRS) in the Diagnosis and Testing portion of this section.
z Key in OFF position.
z Disconnect: RCM C2041.
z Make sure the RCM C2041 pin 10 and pin 13 connector slots are
empty and no connection is made when connected to the RCM.
z Are the RCM C2041 pin 10 and pin 13 connector slots empty? Yes
GO to
C3 .
No
REPAIR any
concern found at
the RCM C2041
pin 10 and pin 13
connector slots.
GO to C6 .
C3 CHECK THE VEHICLE IDENTIFICATION PIN NO. 3
NOTE:
For this vehicle application, RCM C2041 pin 14, circuit 611
(WH/OG) should be connected to ignition voltage.
z Measure the voltage at RCM C2041 pin 14, circuit 611 (WH/OG),
harness side and ground. Yes
GO to
C4 .
No
REPAIR the
circuit. GO to C6 . Klj . 8 ba
462003 Mustang Workshop Manual
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D2 CHECK THE DRIVER AIR BAG MODULE
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section.
The air bag restraint system diagnostic tools must be removed
and the air bag modules reconnected when the system is
reactivated to avoid non- deployment in a collision, resulting in
possible personal injury. NOTE: Diagnostics or repairs are not to
be performed on a seat equipped with a seat side air bag with the
seat in the vehicle. Prior to attempting to diagnose or repair a seat
concern when equipped with a seat side air bag, the seat must be
removed from the vehicle and the restraint system diagnostic tools
must be installed in the seat side air bag electrical connectors. The
restraint system diagnostic tools must be removed prior to
operating the vehicle over the road. NOTE: After diagnosing or
repairing an SRS, the restraint system diagnostic tools must be
removed before operating the vehicle over the road. NOTE:
After diagnosing or repairing a seat system, the restraint system
diagnostic tools must be removed before operating the vehicle
over the road. NOTE: The SRS must be fully operational and free
of faults before releasing the vehicle to the customer.
z Key in OFF position.
z Deactivate the system. Refer to Air Bag Supplemental Restraint System (SRS) in the Diagnosis and Testing portion of this section.
z Key in OFF position.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1887 retrieved? Yes
GO to
D3 .
No
INSTALL a new
driver air bag
module. GO to D6 .
D3 CHECK THE DRIVER AIR BAG MODULE CIRCUIT
z
Key in OFF position.
z Disconnect: RCM C2041.
z NOTE: Do not separate or remove shorting bars from RCM C2041.
z Measure the resistance between RCM C2041 pin 3, circuit 614
(GY/OG), harness side and RCM C2041 pin 21, circuit 397
(BK/WH), harness side.
z Is the resistance less than 10,000 ohms? Yes
GO to
D4 .
No
INSTALL a new
RCM. GO to D6 .
D4 CHECK THE DRIVER AIR BAG MODULE WIRING AND THE
CLOCKSPRING z
Disconnect: Driver Air Bag Module C216.
z Disconnect: Clockspring C218b.
z Inspect all crimps, terminals, wires and connectors in circuit 614
(GY/OG) feeding the RCM pin 3, circuit 615 (GY/WH) feeding pin 4,
the clockspring C218b. Check for pinched wires and damaged
connector pin terminals.
z Was any damage found? Yes
REPAIR as
necessary. GO to
D6
.
No
GO to D6 . Klj . 11 ba
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A driver air bag circuit short to battery or ignition can be caused by:
za short to battery or ignition on circuit 614 (GY/OG).
z a short to battery or ignition on circuit 615 (GY/WH).
z a short to battery or ignition on the clockspring.
z a short to battery or ignition on the driver air bag module.
z an RCM internal concern.
PINPOINT TEST E: LFC 15/DTC B1916 — DRIVER AIR BAG CIRCUIT
SHORTED TO BATTERY OR IGNITION Test Step Result / Action to
Take E1 CHECK FOR A HARD OR INTERMITTENT DTC
z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this
pinpoint test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1916 retrieved during the on- demand self test? Yes
This is a hard fault.
The fault condition
is still present. This
fault cannot be
cleared until it is
corrected and the
DTC is no longer
retrieved during the
on-
demand self
test. GO to E2 .
No
This in an
intermittent fault.
The fault condition
is not present at this
time. GO to E5 .
E2 CHECK THE DRIVER AIR BAG MODULE
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section.
The air bag restraint system diagnostic tools must be removed
and the air bag modules reconnected when the system is
reactivated to avoid non- deployment in a collision, resulting in
possible personal injury. NOTE: Diagnostics or repairs are not to
be performed on a seat equipped with a seat side air bag with the
seat in the vehicle. Prior to attempting to diagnose or repair a seat
concern when equipped with a seat side air bag, the seat must be
removed from the vehicle and the restraint system diagnostic tools
must be installed in the seat side air bag electrical connectors. The
restraint system diagnostic tools must be removed prior to
operating the vehicle over the road. NOTE: After diagnosing or
repairing an SRS, the restraint system diagnostic tools must be
removed before operating the vehicle over the road. NOTE:
After diagnosing or repairing a seat system, the restraint system
diagnostic tools must be removed before operating the vehicle Yes
GO to
E3 .
No
INSTALL a new
driver air bag
module. GO to E6 . Klj . 13 ba
462003 Mustang Workshop Manual
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F1 CHECK FOR A HARD OR INTERMITTENT DTC
z
Key in OFF position.
z Connect the diagnostic tool. Scan Tool
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
Retrieve/Clear Continuous DTCs.
z Retrieve and record any continuous DTCs for use later in this
pinpoint test.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1888 retrieved during the on- demand self test? Yes
This is a hard fault.
The fault condition
is still present. This
fault cannot be
cleared until it is
corrected and the
DTC is no longer
retrieved during the
on-
demand self
test. GO to F2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
F5 .
F2 CHECK THE PASSENGER AIR BAG MODULE
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section.
The air bag restraint system diagnostic tools must be removed
and the air bag modules reconnected when the system is
reactivated to avoid non- deployment in a collision, resulting in
possible personal injury. NOTE: Diagnostics or repairs are not to
be performed on a seat equipped with a seat side air bag with the
seat in the vehicle. Prior to attempting to diagnose or repair a seat
concern when equipped with a seat side air bag, the seat must be
removed from the vehicle and the restraint system diagnostic tools
must be installed in the seat side air bag electrical connectors. The
restraint system diagnostic tools must be removed prior to
operating the vehicle over the road. NOTE: After diagnosing or
repairing an SRS, the restraint system diagnostic tools must be
removed before operating the vehicle over the road. NOTE: After
diagnosing or repairing a seat system, the restraint system
diagnostic tools must be removed before operating the vehicle
over the road. NOTE: The SRS must be fully operational and free of
faults before releasing the vehicle to the customer.
z Key in OFF position.
z Deactivate the system. Refer to Air Bag Supplemental Restraint System (SRS) in the Diagnosis and Testing portion of this section.
z Key in OFF position.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1888 retrieved? Yes
GO to
F3 .
No
INSTALL a new
passenger air bag
module. GO to F6 .
F3 CHECK THE PASSENGER AIR BAG MODULE CIRCUIT
z
Key in OFF position.
z Disconnect: RCM C2041.
z NOTE: Do not separate or remove shorting bars from RCM C2041.
z Measure the resistance between RCM C2041 pin 6, circuit 607
(LB/OG), harness side and RCM C2041 pin 21, circuit 397 (BK/WH),
harness side. Yes
GO to
F4 .
No
INSTALL a new
RCM. GO to F6 . Klj . 16 ba
462003 Mustang Workshop Manual
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G2 CHECK THE PASSENGER AIR BAG MODULE
WARNING: If the supplemental restraint system (SRS) is
being serviced, the system must be deactivated and restraint
system diagnostic tools must be installed. Refer to Air Bag Supplemental Restraint System (SRS) in this section.
The air bag restraint system diagnostic tools must be removed
and the air bag modules reconnected when the system is
reactivated to avoid non- deployment in a collision, resulting in
possible personal injury. NOTE: Diagnostics or repairs are not to
be performed on a seat equipped with a seat side air bag with the
seat in the vehicle. Prior to attempting to diagnose or repair a seat
concern when equipped with a seat side air bag, the seat must be
removed from the vehicle and the restraint system diagnostic tools
must be installed in the seat side air bag electrical connectors. The
restraint system diagnostic tools must be removed prior to
operating the vehicle over the road. NOTE: After diagnosing or
repairing an SRS, the restraint system diagnostic tools must be
removed before operating the vehicle over the road. NOTE: After
diagnosing or repairing a seat system, the restraint system
diagnostic tools must be removed before operating the vehicle
over the road. NOTE: The SRS must be fully operational and free of
faults before releasing the vehicle to the customer.
z Key in OFF position.
z Deactivate the system. Refer to Air Bag Supplemental Restraint System (SRS) in the Diagnosis and Testing portion of this section.
z Key in OFF position.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool: On-
Demand Self Test.
z Was DTC B1925 retrieved? Yes
GO to
G3 .
No
INSTALL a new
passenger air bag
module. GO to G6 .
G3 CHECK THE PASSENGER AIR BAG MODULE CIRCUIT
z
Key in OFF position.
z Disconnect: Passenger Air Bag Module Restraint System Diagnostic
Tool.
z Disconnect: RCM C2041.
z Key in ON position.
z NOTE: Do not separate or remove shorting bars from RCM C2041.
z Measure the voltage between RCM C2041 pin 6, circuit 607
(LB/OG), harness side and ground; and between RCM C2041 pin 7,
circuit 616 (PK/BK), harness side and ground.
z Are the voltages less than 0.2 volt? Yes
INSTALL a new
RCM. GO to
G6 .
No
GO to G4 .
G4 CHECK THE PASSENGER AIR BAG MODULE WIRING
z
Inspect all crimps, terminals, wires and connectors in circuit 607
(LB/OG) feeding the RCM pin 6, circuit 616 (PK/BK) feeding pin 7.
Check for pinched wires and damaged connector pin terminals.
z Was any damage found? Yes
REPAIR as
necessary. GO to
G6
. Klj . 19 ba
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