key FORD MUSTANG 2003 Workshop Manual

z
Is the resistance less than 5 ohms? A12 CHECK CIRCUIT 902 (YE) FOR AN OPEN
z
Disconnect: Lower Relay C4064.
z Measure the resistance between lower relay C4064 pin 30, circuit
902 (YE), harness side and convertible top motor C4062, circuit
902 (YE), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new lower
relay. TEST the
system for normal
operation.
No
REPAIR the circuit.
TEST the system for
normal operation.
A13 CHECK THE LOWER INPUT TO THE MOTOR
z
Key in ON position.
z Measure the voltage between convertible top motor C4062, circuit
902 (YE), harness side and ground.
z Depress and hold the convertible top switch in the LOWER
position.
z Is the voltage greater than 10 volts? Yes
GO to
A14 .
No
INSTALL a new lower
relay. TEST the
system for normal
operation. A14 CHECK THE CONVERTIBLE TOP MOTOR RAISE CIRCUIT
z
Key in OFF position.
z Measure the resistance between convertible top motor C4062,
circuit 903 (RD), harness side and ground. Yes
GO to
A16 .
No
GO to A15 . Klj . 6 ba
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PINPOINT TEST B: THE CONVERTIBLE TOP HESITATES/COMES UP
UNEVEN z
Is the resistance less than 5 ohms? A15 CHECK CIRCUIT 903 (RD) FOR AN OPEN
z
Disconnect: Raise Relay C4063.
z Measure the resistance between raise relay C4063 pin 30, circuit
903 (RD), harness side and convertible top motor C4062, circuit
903 (RD), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new raise
relay. TEST the
system for normal
operation.
No
REPAIR the circuit.
TEST the system for
normal operation.
A16 CHECK THE RAISE INPUT TO THE MOTOR
z
Key in ON position.
z Depress and hold the convertible top switch in the RAISE position.
z Measure the voltage between convertible top motor C4062, circuit
903 (RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new
convertible top motor;
REFER to
Hydraulic System, Lift Cylinder
and Motor in this
section. TEST the
system for normal
operation.
No
INSTALL a new raise
relay. TEST the
system for normal
operation. Test Step Result / Action to Take
B1 CHECK THE CONVERTIBLE TOP UP/DOWN
OPERATION NOTE:
The parking brake must be applied for the Yes Klj . 7 ba
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PINPOINT TEST C: THE CONVERTIBLE TOP DOES NOT RAISE OR
DOES NOT GO UP ALL THE WAY
PINPOINT TEST D: THE CONVERTIBLE TOP HYDRAULIC SYSTEM convertible top system to operate.
z Key in ON position.
z Actuate the convertible top switch to the LOWER
and RAISE positions.
z Did the convertible top operate to the full down
and full up position without hesitating? ADJUST the convertible top linkage.
TEST the system for normal
operation.
No
GO to
B2 .
B2 CHECK THE MOTOR OPERATION
z
Gain access to the convertible top motor/pump
assembly.
z Operate the convertible top to the LOWER and
RAISE positions while listening to the motor.
z Did the motor stop and then continue at any
time? Yes
Go To Pinpoint Test A
.
No
GO to B3 .
B3 CHECK THE CONVERTIBLE TOP LINKAGE
z
Operate the convertible top to the LOWER and
RAISE positions while observing the convertible
top linkage.
z Did the linkage operate smoothly without
binding? Yes
Go To Pinpoint Test D
.
No
ADJUST the convertible top linkage.
TEST the system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE CONVERTIBLE TOP OPERATION
NOTE:
The parking brake must be applied for the
convertible top system to operate.
z Key in ON position.
z Actuate the convertible top switch to the RAISE
position.
z Did the motor operate? Yes
GO to
C2 .
No
Go To Pinpoint Test A .
C2 CHECK THE CONVERTIBLE TOP LINKAGE
z
Operate the convertible top to the LOWER and
RAISE positions while observing the convertible
top linkage.
z Did the linkage bind and prevent the
convertible top from raising? Yes
ADJUST the convertible top linkage.
TEST the system for normal
operation.
No
Go To Pinpoint Test D
.
Test Step Result / Action to Take
D1 CHECK THE FLUID LEVEL
NOTE:
The fluid level should be even
with the bottom of the filler plug hole.
NOTE: Place an absorbent cloth
below the filler plug when checking
the fluid level.
z Remove the filler plug and check the Yes
GO to
D3 .
No
GO to D2 . Klj . 8 ba
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Driver Air Bag Module
The driver air bag module:
zis installed as an assembly.
z is mounted in the center of the steering wheel.
Clockspring
The clockspring: zis mounted on the steering column, behind the steering wheel.
z provides a continuous electrical path from the restraints control module (RCM) to the driver air
bag.
Passenger Air Bag Module
The passenger air bag module: zis installed as an assembly.
z is mounted in the RH side of the instrument panel.
Restraints Control Module (RCM)
The restraints control module (RCM) performs the following functions: zsignals the inflators to deploy the air bags in the event of a deployable crash.
z monitors the air bag supplemental restraint system (SRS) for faults.
z illuminates the air bag indicator if a fault is detected.
z flashes the air bag indicator to indicate the lamp fault code (LFC) detected.
z communicates through the data link connector (DLC) the current or historical diagnostic trouble
codes (DTCs).
z signals the generic electronic module (GEM) to activate a chime if the air bag indicator is not
available and another SRS fault exists.
NOTE: The safing sensor is internal to the RCM and is not repaired separately.
The RCM monitors the SRS for possible faults. If a fault is detected while the ignition switch is in the
RUN position, the RCM will illuminate the air bag indicator located in the instrument cluster.
When the ignition is cycled (turned off and then on), the air bag indicator will begin its prove out
sequence. During prove out the air bag indicator will illuminate for six seconds, go off for two seconds
and then, if a system fault exists, flash the two- digit LFC. The air bag indicator will flash the LFC five
times, then it will remain illuminated for the rest of the key cycle. The RCM will also communicate the Klj . 2 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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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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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 this section.
z Key in OFF position.
z Connect: RCM C2041.
z Make sure RCM C2041 is fully connected and the red locking tab is
engaged.
z Is RCM C2041 fully connected and are the red locking tabs
engaged? A3 CHECK THE RCM CONNECTOR
z
Key in OFF position.
z Disconnect: RCM C2041.
z Inspect C2041 component side for a worn, or damaged camming
beam. Inspect for foreign material.
z NOTE: The shorting bars can be accessed by prying out the blue
cover from the harness side of the connector.
z Inspect C2041 harness side for worn, damaged, or dislodged shorting
bar at pins 20 and 21. Inspect for foreign material.
z Were any connector concerns found? Yes
CORRECT
connector
concerns. GO to
A7
.
No
GO to A4 .
A4 CHECK THE IGNITION CIRCUIT 611 (WH/OG) FOR AN OPEN
z
Key in ON position.
z Measure the voltage between RCM C2041 pin 2, circuit 611
(WH/OG), harness side and ground. Yes
GO to
A5 .
No
REPAIR the
circuit. GO to A7 . Klj . 3 ba
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z
Is the voltage between 9 and 16 volts? A5 CHECK THE GROUND CIRCUIT 397 (BK/WH) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between RCM C2041 pin 21, circuit 397
(BK/WH), harness side and a sheet metal ground near the RCM.
z Is the resistance less than 10 ohms? Yes
GO to
A6 .
No
REPAIR the
circuit. GO to A7 .
A6 CHECK CIRCUIT 608 (BK/YE) FOR A SHORT TO GROUND
z
Connect: RCM C2041.
z Disconnect: Instrument Cluster C220a.
z Measure the resistance to ground at instrument cluster C220a pin 12,
circuit 608 (BK/YE), harness side.
z Is the resistance less than 10,000 ohms? Yes
REPAIR the
circuit. GO to
A7 .
No
INSTALL a new
RCM. GO to A7 .
A7 CHECK FOR ADDITIONAL DTCs
z
Refer to the continuous DTCs recorded during Step A1.
z Were any continuous DTCs retrieved during Step A1? 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 Klj . 4 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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test? This is an intermittent fault.
The fault condition is not
present at this time. GO to
B6
.
B2 INSPECT THE RCM MOUNTING, MOUNTING BRACKET
AND MOUNTING SURFACE z
Remove the RCM. Refer to Restraints Control Module (RCM) in the Removal and Installation portion of this
section.
z Visually inspect the RCM, mounting bracket and mounting
surface for damage, corrosion or dirt.
z Inspect the RCM mounting and make sure that the
retaining bolts are fully seated and tightened correctly.
Refer to Restraints Control Module (RCM) in the Removal
and Installation portion of this section for correct tightening
torque.
z Was a significant amount of corrosion or dirt found,
the RCM mounting bracket attached to the mounting
surface incorrectly or were the three RCM retaining
bolts not fully seated and tightened correctly? Yes
Make sure the RCM,
mounting bracket and
mounting surface are free of
damage, corrosion or dirt and
the three retaining bolts are
fully seated and correctly
tightened. Reattach the RCM
and mounting bracket to the
mounting surface. GO to
B7 .
No
GO to B3 .
B3 CHECK THE RCM HARNESS CONNECTION
z
Check the RCM harness connection.
z Is the RCM harness connector connected to the RCM
correctly? Yes
GO to
B4 .
No
ATTACH the RCM harness
connector correctly. GO to
B7 .
B4 CHECK THE VEHICLE CHASSIS GROUND
z
Measure the resistance between a known good chassis
ground and the mounting surface of the RCM.
z Is the resistance greater than 100 ohms? Yes
REPAIR the chassis
grounding system. GO to
B7 .
No
GO to B5 .
B5 CHECK THE GROUND CIRCUIT 397 (BK/WH) FOR AN
OPEN z
Key in OFF position.
z Disconnect: RCM C2041.
z Measure the resistance between RCM C2041 pin 21,
circuit 397 (BK/WH), harness side and a sheet metal
ground near the RCM.
z Is the resistance greater than 100 ohms? Yes
REPAIR the circuit. GO to
B7
.
No
INSTALL a new RCM. GO to
B7 .
B6 CHECK FOR AN INTERMITTENT FAULT
z
Refer to the continuous DTCs recorded during Step B1. Yes Klj . 6 ba
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