service indicator FORD MUSTANG 2003 Owner's Manual

a
DTC: Diagnostic Trouble Code, retrieved using a scan tool.
b LFC: Lamp fault code, flashed on air bag indicator.
c Tone will sound only if additional DTCs are present.
Inspection and Verification 1. Verify the customer concern by checking the air bag indicator in the instrument cluster. Refer to Prove Out the System in this section.
2. Visually inspect for obvious signs of mechanical and electrical damage using the following chart:
3. If the concern is not visually evident, use the scan tool to retrieve diagnostic trouble codes (DTCs) and perform the on- demand self test.
4. WARNING: The restraint system diagnostic 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.
If the on- demand self test is passed and no DTCs are retrieved, GO to Symptom Chart .
5. If DTCs are retrieved, proceed to the Restraints Control Module (RCM) Diagnostic Trouble Code (DTC) Priority Table.
Symptom Chart — — — No Communication with the Restraints Control Module Go To Pinpoint
Test P .
Visual Inspection Chart Mechanical Electrical
z
Damaged restraints control module (RCM) bracket z
Open fuse(s)
z Damaged wiring harness
z Loose or corroded connectors
z Circuitry open/shorted Symptom Chart
Condition
Possible Sources Action
z Air bag warning indicator is
illuminated continuously z
Circuitry.
z Worn or damaged
connector component.
z RCM.
z Instrument cluster. z
Go To Pinpoint Test A .
z Air bag indicator flashing zAir bag SRS system
fault. z
REFER to DTC
Priority Table.
z Audible tone — DTCs
retrieved z
Air bag SRS system
fault. z
Go To Pinpoint Test N .
z Go To Pinpoint Test O .
z No communication with the zScan Tool. zGo To Pinpoint Klj . 4 ba
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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
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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 K: LFC 35/DTC B1935 —
Passenger Air Bag Circuit Resistance Low
Normal Operation
The restraints control module (RCM) monitors the resistance of the passenger air bag ignitor by
measuring the resistance between pins 6 and 7. If the RCM detects low resistance between these
pins, it will store a diagnostic trouble code (DTC) B1935 in memory and flash a lamp fault code (LFC)
35 (or higher priority code if one exists) on the air bag indicator.
Possible Causes
Passenger air bag low resistance can be caused by:
za short in the wiring harness.
z a low resistance in the passenger air bag module.
z an RCM internal concern.
z a worn or damaged connector shorting bar or camming beam.
PINPOINT TEST K: LFC 35/DTC B1935 — PASSENGER AIR BAG
CIRCUIT RESISTANCE LOW (SRS) in this
section. CLEAR all
DTCs. Test Step Result / Action to
Take K1 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 B1935 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 K2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
K4 .
K2 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. Yes
GO to
K3 .
No
INSTALL a new Klj . 29 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 B1892 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
L2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
L5 .
L2 CHECK THE AIR BAG TONE WARNING INDICATOR CIRCUIT
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 Disconnect: RCM C2041.
z Disconnect: GEM C201e.
z Measure the resistance between RCM C2041 pin 26, circuit 1083
(LB/BK), harness side and RCM C2041 pin 21, circuit 397 (BK/WH),
harness side. Yes
REPAIR the
circuit. GO to
L6 .
No
GO to L3 . Klj . 32 ba
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An air bag tone warning indicator circuit short to battery or ignition can be caused by:
za short to battery or ignition on circuit 1083 (LB/BK).
z a damaged or inoperative GEM.
z an RCM internal concern.
PINPOINT TEST M: DTC B1891 — AIR BAG TONE WARNING
INDICATOR CIRCUIT SHORTED TO BATTERY OR IGNITION Test Step Result / Action to
Take M1 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 B1891 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
M2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
M4 .
M2 CHECK THE AIR BAG TONE WARNING INDICATOR CIRCUIT
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. Yes
GO to
M3 .
No
REPAIR the
circuit. GO to M5 . Klj . 35 ba
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circuit, it will store a diagnostic trouble code (DTC) B1870 in memory.
If the RCM detects an air bag indicator failure in addition to another SRS failure, the RCM will send a
signal to the generic electronic module (GEM) to produce five sets of five tone bursts.
Possible Causes
An air bag indicator short to battery condition can be caused by:
zdamaged wiring on circuit 608 (BK/YE).
z an instrument cluster malfunction.
z an RCM internal concern.
PINPOINT TEST O: DTC B1870 — AIR BAG INDICATOR SHORTED
TO BATTERY Test Step Result / Action to
Take O1 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 B1870 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
O2 .
No
This is an
intermittent fault.
The fault condition
is not present at
this time. GO to
O4 .
O2 CHECK THE AIR BAG INDICATOR CIRCUIT
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 Yes
INSTALL a new
RCM. GO to
O5 .
No
GO to O3 . Klj . 41 ba
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