Test G FORD MUSTANG 2003 Workshop Manual

DIAGNOSIS AND TESTING
Air Bag Supplemental Restraint System (SRS)
Refer to Wiring Diagrams Cell
46 , Air Bag for schematic and connector information.
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.
Diagnosing Customer Concerns Without Hard DTCs
If a lamp fault code (LFC) is reported by the customer but is not present when the vehicle comes in for
service, follow the Diagnostic Instructions procedure in this section to identify the intermittent DTC.
Once the DTC is known, read the Normal Operation section of the pinpoint test for the DTC involved.
zFollow the deactivation procedure in this section.
z Determine the location of components involved in creating that code.
z Perform a thorough visual inspection of:
„components.
„ connectors.
„ splices and wiring harnesses.
„ pinched wires.
„ worn insulation on conductors.
Refer to the Possible Causes section of the pinpoint test for the DTC involved, which lists the common
concerns that relate to the DTC. Concerns are listed according to priority.
Diagnosing Customer Concerns with Hard DTCs
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. SECTION 501-
20B: Supplemental Restraint System 2003 Mustang Workshop Manual Special Tool(s)
Diagnostic Tool, Restraint
System
418-
F088 (105- R0012) Klj . 1 ba
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Most air bag supplemental restraint system (SRS) diagnostic procedures will require the use of the
deactivation and reactivation procedures in this section.
The deactivation and reactivation require the installation and removal of restraint system diagnostic
tools. These procedures require removal of driver air bag module, and the disconnection of the
passenger air bag module. This reduces the risk of deployment of air bag modules and safety belt
pretensioners while diagnostics are being carried out.
Restraint system diagnostic tools are required to carry out diagnosis and testing of the supplemental
restraint system (SRS). It is not acceptable to short-circuit the air bag module connections with a
jumper wire. If a jumper wire is used to short- circuit the air bag module connections, a lamp fault code
(LFC) will be displayed.
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.
The reactivation procedure requires the removal of any restraint system diagnostic tools installed and
the reconnection of any air bag modules disconnected.
Deactivation Procedure
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.
1. WARNING: To avoid accidental deployment and possible personal injury, the
backup power supply must be depleted before repairing or replacing any front or side air
bag supplemental restraint system (SRS) components and before servicing, replacing,
adjusting or striking components near the front or side air bag sensors, such as doors,
instrument panel, console, door latches, strikers, seats and hood latches.
Please refer to the appropriate vehicle shop manual to determine location of the front air
bag sensors.
The side air bag sensors are located at or near the base of the B- pillar. Klj . 2 ba
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steering column.
4. WARNING: Carry a live air bag module with the air bag and trim cover pointed away
from your body. This will reduce the risk of injury in the event of an accidental
deployment.
Install the driver air bag module. Refer to Driver Air Bag Module in this section.
5. 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.
Remove the restraint system diagnostic tool from the vehicle harness connector at the
passenger air bag module.
6. Connect the passenger air bag module electrical connector.
7. Reconnect the battery ground cable. For additional information, refer to Section 414 - 01 .
8. Prove out the system.
Prove Out Procedure
Turn the ignition switch from the OFF to the RUN position and visually monitor the air bag indicator
with the air bag modules or restraint system diagnostic tools installed. The air bag indicator will light
continuously for approximately six seconds and then turn off. If an air bag supplemental restraint
system (SRS) fault is present, the air bag indicator will either: zfail to light.
z remain lit continuously.
z flash.
The flashing might not occur until approximately 30 seconds after the ignition switch has been turned
from the OFF to the RUN position. This is the time required for the restraints control module (RCM) to
complete the testing of the SRS. If the air bag indicator is inoperative and an SRS fault exists, a chime
will sound in a pattern of five sets of five beeps. If this occurs, the air bag indicator will need to be
repaired before diagnosis can continue.
Glossary
Restraint System Diagnostic Tool
Restraint system diagnostic tools are used to simulate air bag module connections to the system.
Disconnect the Component
Disconnect the component means disconnect the component vehicle harness connector. It does not
mean remove the component. Do not reconnect a disconnected component unless instructed to do so. Deactivate the System Klj . 4 ba
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DIAGNOSIS AND TESTING
Diagnostic Instructions —
Air Bag Supplemental Restraint
System (SRS)
The symptom chart can be used to help locate the air bag supplemental restraint system (SRS)
concerns if no diagnostic trouble codes (DTCs) are retrieved and the listed symptoms are observed.
Whether or not the listed symptoms are observed, always perform the following.
1. Retrieve all DTCs stored in the restraints control module (RCM) memory. Refer to Retrieve/Clear Continuous DTCs in this section.
2. Run the On- Demand Self Test to determine what DTCs are currently being sensed by the
restraints control module (RCM) (14B321). Refer to On- Demand Self Test in this section.
3. If the stored DTCs are different than the current DTCs, always repair the current DTCs first.
4. If memory displays different continuous DTCs than the On- Demand Self-Test, perform in the
following order:
z On- Demand Self- Test.
z Memory (Retrieve/Clear Continuous DTCs).
A DTC can indicate several concerns. The DTCs are to assist in system diagnosis and are not to be
considered definitive. Always refer to the pinpoint test corresponding to the DTC to determine where
the concern lies and to repair the concern correctly.
The SRS diagnostics can be divided into three sections.
zDiagnostic test modes
z PID/data monitor and record
z Active command modes
Diagnostic Test Modes
Two menu options are available under the diagnostic test modes.
zRetrieve/Clear Continuous DTCs.
z On- Demand Self Test.
SECTION 501-
20B: Supplemental Restraint System 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool Klj . 1 ba
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Retrieve/Clear Continuous DTCs
During vehicle operation, the restraints control module (RCM) will detect and store both intermittent
and hard fault DTCs in nonvolatile memory. The DTC strategy employed by the RCM incorporates a
time-out scheme for determining when a concern exists in the system. This requires a concern to exist
for up to one minute in the system before the RCM will detect it. For the RCM to determine that a
concern no longer exists, the concern must be absent for up to one minute. The actual detection time-
outs vary with each DTC. The DTCs can be retrieved with a scan tool. Any DTCs stored in the RCM
will be displayed on the scan tool along with a brief description of the DTC. If no DTCs are present, the
scan tool will display a SYSTEM PASSED message. This option can also be used to clear DTCs from
the RCM memory, as long as the concern no longer exists. Once 128 key cycles have been recorded
since the concern was last detected, the DTC will automatically be removed from memory.
To retrieve or clear DTCs, follow these steps.
1. Connect the scan tool to the data link connector (DLC).
2. Turn the ignition switch to the RUN position.
3. Follow manufacturer's instructions for the scan tool being used.
4. All continuous DTCs will be displayed. Before proceeding with the clearing operation, make note of the DTCs displayed because, once cleared, they cannot be retrieved.
5. The scan tool will retrieve DTCs again after clearing DTCs and, if any remain, they will be displayed. Hard DTCs will be redisplayed after clearing DTCs since they cannot be cleared from
the RCM.
On- Demand Self Test
The On- Demand Self Test option is used to verify that no electrical concerns exist with the air bag
supplemental restraint system (SRS). Upon entering the self test, the restraints control module (RCM)
will make an electrical check of each electrical component in the system. If a concern is detected, a
DTC is displayed on the scan tool with a brief description of the DTC. Concerns detected during the
self test are not stored in memory, unless the same concern was also detected during normal vehicle
operation. The self test should always be run after any repair to verify that the repair was successful.
To run the On- Demand Self Test, follow these steps:
6. Connect a scan tool to the data link connector (DLC).
7. Turn the ignition switch to the RUN position.
8. Follow manufacturer's instructions for the scan tool being used.
9. The RCM will run the On- Demand Self Test and display on- demand DTCs (reflecting hard
system concerns) on the screen.
PID/Data Monitor and Record
The PID/Data Monitor and Record option allows the scan tool operator to read the state of several
parameter IDs (PIDs) to aid in diagnosing the system. PIDs are real time measurements of parameters
such as voltages, resistances, etc., calculated by the restraints control module (RCM) and sent to the
scan tool for display. Many of the PIDs supported by the RCM are calculated periodically and are,
therefore, not true real time readings.
To retrieve PIDs, follow these steps: 1. Connect the scan tool to data link connector (DLC). Klj . 2 ba
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2. Turn the ignition switch to the RUN position.
3. Follow manufacturer's instructions for the scan tool being used.
4. PIDs are continuously updated on the display.
Active Commands
This command allows the technician to verify operation of the air bag indicator and chime. When the
air bag output command is executed, the indicator and the chime are activated simultaneously for
approximately four seconds. Both devices are deactivated automatically.
Restraints Control Module (RCM) Diagnostic Trouble Code (DTC) Priority Table DTC
a LFC
b LFC
Priority Description Action To
Take — — 1 The Air Bag Indicator is Illuminated Continuously —
RCM
Disconnected, Inoperative, or Lost/Low Ignition Feed Go To Pinpoint
Test A .
B1342 24 2 RCM Is Faulted INSTALL a
new RCM.
B1231 19 3 RCM Crash Data Memory Full INSTALL a
new RCM.
B1921 21 4 RCM Bracket Ground Resistance High Go To Pinpoint
Test B .
C1414 29 5 Incorrect Vehicle Identification Code Go To Pinpoint
Test C .
B1887 15 6 Driver Air Bag Circuit Shorted to Ground Go To Pinpoint
Test D .
B1916 15 7 Driver Air Bag Circuit Shorted to Battery or Ignition Go To Pinpoint
Test E .
B1888 16 8 Passenger Air Bag Circuit Shorted to Ground Go To Pinpoint
Test F .
B1925 16 9 Passenger Air Bag Circuit Shorted to Battery or Ignition Go To Pinpoint
Test G .
B1932 32 10 Driver Air Bag Circuit Resistance High Go To Pinpoint
Test H .
B1933 33 11 Passenger Air Bag Circuit Resistance High Go To Pinpoint
Test I .
B1934 34 12 Driver Air Bag Circuit Resistance Low Go To Pinpoint
Test J .
B1935 35 13 Passenger Air Bag Circuit Resistance Low Go To Pinpoint
Test K .
B1892 — 17 Air Bag Tone Warning Indicator Circuit Shorted to
Ground or Open Go To Pinpoint
Test L .
B1891 — 18 Air Bag Tone Warning Indicator Circuit Shorted to Battery
or Ignition Go To Pinpoint
Test M .
B1869 Tone
c 19 Air Bag Indicator Inoperative Go To Pinpoint
Test N .
B1870 Tone
c 20 Air Bag Indicator Shorted to Battery Go To Pinpoint
Test O . Klj . 3 ba
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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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restraints control module
zData Link Connector
(DLC).
z RCM.
z Circuitry. Test P . Klj . 5 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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