power steering FORD MUSTANG 2003 Workshop Manual

DIAGNOSIS AND TESTING
Speed Control
Refer to Wiring Diagrams Cell
31 , Speed Control for schematic and connector information.
Principles of Operation
The speed control system is designed to maintain vehicle speed above 48 km/h (30 mph). After the
ON switch is depressed, depressing the SET/ACCEL switch will activate the speed control servo. To
increase a set speed, either depress and hold for continuous acceleration, or momentarily tap the
SET/ACCEL switch for 1.6 km/h (1 mph) acceleration increments. To decrease a set speed, depress
and hold the COAST switch until the target speed is reached, or momentarily tap the COAST switch
for 1.6 km/h (1 mph) deceleration increments. When the speed control system has been disabled by
tapping the brake pedal, the RESUME switch can be depressed and the vehicle will return to the
original set speed if the vehicle is traveling over 48 km/h (30 mph) and the OFF switch has not been
depressed.
NOTE: The deactivator switch is provided as an additional safety feature. Normally, when the brake
pedal is depressed, an electrical signal from the brake lamp circuit to the speed control servo will
deactivate the system. Under increased brake pedal effort, the deactivator switch will open and
remove power to the speed control servo, releasing the throttle independent of the speed control
servo.
NOTE: The air bag sliding contract provides the electrical interface between the steering column wiring
and the speed control actuator switches in the steering wheel.
The inputs to the speed control servo are the:
zvehicle speed signal.
SECTION 310-
03: Speed Control 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool 73 Digital Multimeter or
equivalent
105-
R0051 Breakout Box, EEC-V Control
System 418-049, or equivalent
014- 00950 Klj . 1 ba
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The boost pressure gauge on the instrument cluster receives and measures the boost pressure
directly from the intake manifold. The boost pressure gauge will display between 0.0-
0.48 kpa (0.0-10
psi) boost pressure dependent upon accelerator position, engine load, and engine rpm.
LOW FUEL Level Indicator
The low fuel level indicator is hardwired from the fuel sender to the instrument cluster. The instrument
cluster will illuminate the low fuel indicator when the usable fuel quantity is less than 1/8 tank (15%) of
fuel tank capacity.
Oil Pressure Gauge
The oil pressure gauge is hardwired from the oil pressure switch to the instrument cluster. The oil
pressure gauge will indicate either normal or no oil pressure.
CHECK FUEL CAP
The CHECK FUEL CAP indicator is used to indicate significant leaks in the fuel tank evaporative
system due to a loose fuel cap. Fuel tank pressure is monitored by the PCM. If a leak is detected the
PCM signals a fault to the instrument cluster via the SCP network. Once the PCM has detected a
loose fuel cap and the CHECK FUEL CAP indicator is illuminated, the indicator will remain illuminated
until the fuel cap is secured and the vehicle has been running for several minutes. For additional
information, refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
BRAKE Warning Indicator
The BRAKE warning indicator activates when the generic electronic module (GEM) detects the ignition
switch circuits are in the RUN state, when the GEM detects low brake fluid level, or that the parking
brake is applied. The BRAKE warning indicator will prove out starting when the GEM detects that the
ignition circuits have made a transition to RUN or START from OFF, ACC, or keyout and ending when
either three seconds have elapsed or when the GEM detects the ignition circuits have made a
transition to OFF, ACC, or keyout.
Safety Belt Warning Indicator
The safety belt switch is hardwired to the GEM. The safety belt warning indicator will be illuminated
when the GEM sends a ground signal to the instrument cluster.
ABS Warning Indicator
The ABS warning indicator will be illuminated when the anti- lock brake control module sends a ground
signal to the instrument cluster. The prove- out of the ABS indicator is controlled by the anti- lock brake
control module.
SERVICE ENGINE SOON Indicator
The SERVICE ENGINE SOON indicator receives its signal from the PCM over the SCP network. If the
instrument cluster does not receive a message from the PCM within five seconds, the instrument
cluster will illuminate the SERVICE ENGINE SOON indicator and log a diagnostic trouble code (DTC).
High Beam Indicator
The high beam indicator will illuminate when the steering column multifunction switch is in the high
beam position by sending a battery signal to the instrument cluster. Right and Left Turn Indicator Klj . 3 ba
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PINPOINT TEST T: THE TURN/HAZARD INDICATOR IS
NEVER/ALWAYS ON CLUSTER SERVICE ENGINE SOON
INDICATOR ACTIVE COMMAND
z
Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode
on the diagnostic tool: Instrument
Cluster Active Command.
z Trigger the instrument cluster active
command MIL.
z Did the SERVICE ENGINE SOON
indicator illuminate? Yes
REFER to the Powertrain Control/Emissions
Diagnosis (PC/ED) manual.
No
GO to
S2 .
S2 CHECK FOR CORRECT
INSTRUMENT CLUSTER OPERATION z
Disconnect all instrument cluster
connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster
connectors and make sure they seat
correctly.
z Operate the system and verify the
concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument cluster. REFER to
Instrument Cluster
in this section. TEST the
system for normal operation.
No
The system is operating correctly at this time.
Concern may have been caused by a loose or
corroded connector. CLEAR the DTCs. REPEAT
the self- test. Test Step Result / Action to
Take T1 CHECK THE TURN SIGNAL AND HAZARD LAMPS OPERATION
CAUTION: Use the correct probe adapter(s) when making
measurements. Failure to use the correct probe adapter(s) may
damage the connector.
z Key in ON position.
z Operate the left and right turn signals.
z Operate the hazard lamps.
z Do the turn signals and hazard lamps operate correctly? Yes
GO to
T2 .
No
REFER to Section 417 - 01 .
T2 CHECK THE CIRCUIT IN QUESTION —
CIRCUIT 2 (WH/LB) (RH)
OR CIRCUIT 3 (LG/WH) (LH) z
Key in OFF position.
z Disconnect: Instrument Cluster C220a (RH) or C220b (LH).
z Key in ON position.
z Measure the voltage between the instrument cluster C220a pin 3,
circuit 3 (LG/WH), harness side and ground, while the steering
column multifunction switch is placed in the left turn position (LH); or
between the instrument cluster C220b pin 3, circuit 2 (WH/LB),
harness side and ground, while the steering column multifunction
switch is placed in the right turn position (RH). Yes
GO to
T3 .
No
REPAIR the circuit
(s) in question.
TEST the system for
normal operation. Klj . 36 ba
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DIAGNOSIS AND TESTING
Communications Network
Refer to Wiring Diagrams Cell
14 , Multiplex Communication Network for schematic and connector
information.
Principles of Operation
The vehicle has two module communications networks. The standard corporate protocol (SCP) which
is an unshielded twisted pair cable (data bus plus, Circuit 914 [TN/OG] and data bus minus, Circuit 915
[PK/LB]), and the international standards organization (ISO) 9141 network which is a single wire
(Circuit 70 [LB/WH]). The diagnostic tool can connect to both networks through the data link connector
(DLC). This makes diagnosis and testing of these systems easier by allowing one smart tester to be
able to diagnose and control any module on the two networks from one connector. The DLC can be
found under the instrument panel between the steering column and the radio.
The ISO 9141 communication network does not permit inter- module communication. When the
diagnostic tool communicates to modules on the ISO 9141 communication network, the diagnostic tool
must ask for all information; the modules cannot initiate communications.
The SCP network will remain operational even with the severing of one of the bus wires.
Communications will also continue if one of the bus wires is shorted to ground or battery positive
voltage (B+) or if some, but not all, termination resistors are lost.
Unlike the SCP communication network, the ISO 9141 communication network will not function if the
wire is shorted to chassis ground or battery positive voltage (B+). Also, if one of the modules on the
ISO 9141 network loses power or shorts internally, communications to that module will fail.
The powertrain control module (PCM) is on the SCP communication network. The PCM controls the
engine for better fuel economy, emissions control, and failure mode detection and storage. Refer to
Powertrain Control/Emissions Diagnosis (PC/ED) manual Section 3 for diagnosis and testing of the
PCM.
The restraint control module (RCM) is on the ISO 9141 network. The RCM controls the deployment of
the air bags based on sensor input. For additional information, refer to Section 501 - 20B .
SECTION 418-
00: Module Communications Network 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter or
equivalent
105-
R0051 Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool Klj . 1 ba
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DESCRIPTION AND OPERATION
Anti-
Theft — Passive Anti- Theft System (PATS)
The passive anti- theft system (PATS) contains the following components:
z theft indicator
z encoded ignition key
z transceiver module
z instrument cluster
z powertrain control module (PCM)
z standard corporate protocol (SCP) communication network
The PATS uses radio frequency identification technology to deter a driveaway theft. Passive means
that it does not require any activity from the user. This system is known as SecuriLock® in North
America, Safeguard® in the U.K. and PATS in continental Europe. This information can be found in
owners literature.
The PATS uses a specially encoded ignition key. Each encoded ignition key contains a permanently
installed electronic device called a transponder. Each transponder contains a unique electronic
identification code, with over 72 million billion combinations.
Each encoded ignition key must be programmed into the vehicle's instrument cluster (the instrument
cluster is also known as a hybrid electronic cluster [HEC]), before it can be used to start the engine.
There are special diagnostic procedures outlined in the workshop manual that must be carried out if
new encoded ignition keys are to be installed.
The encoded key is larger than a traditional ignition key. The key does not require batteries and should
last the life of the vehicle.
The transceiver module communicates with the encoded ignition key. This module is located behind
the steering column shroud and contains an antenna connected to a small electronics module. During
each vehicle start sequence, the transceiver module reads the encoded ignition key identification code
and sends the data to the instrument cluster.
The control functions are contained in the instrument cluster. This module carries out all of the PATS
functions such as receiving the identification code from the encoded ignition key and controlling engine
enable. The instrument cluster initiates the key interrogation sequence when the vehicle ignition switch
is turned to RUN or START.
The PATS uses the PCM to enable or disable the engine. The instrument cluster communicates with
the PCM over the SCP network in order to enable engine operation. The instrument cluster and the
PCM use sophisticated messages in order to prevent a theft. The instrument cluster and the PCM
share security data (when first installed together) that makes them a matched pair. After this security
data sharing, these modules will not function in other vehicles. The shared PCM ID is remembered
even if the battery is disconnected. The instrument cluster also stores the vehicle's key identification
code even if the battery is disconnected. There are special diagnostic procedures outlined in this
workshop manual that may be carried out if either a new instrument cluster or PCM needs to be
installed.
All elements of PATS must be functional before the engine is allowed to start. If any of the components
are not working correctly, the vehicle will not start.
PATS uses a visual theft indicator. This indicator will prove out for three seconds when the ignition SECTION 419-
01: Anti-Theft — PATS 2003 Mustang Workshop Manual Klj . 1 ba
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REMOVAL AND INSTALLATION
Ignition Lock Cylinder —
Non-Functional
Removal and Installation 1. NOTE: Make sure the front wheels are in the straight- ahead position.
Disconnect the battery ground cable (14301) and wait at least one minute to allow the depletion
of the restraint system backup power supply. For additional information, refer to Section 414 -
01 .
2. WARNING: To avoid the risk of serious personal injury, read and follow all
warnings, cautions, notes and instructions in the deactivation procedure.
Deactivate the supplemental restraint system (SRS). For additional information, refer to
Supplemental Restraint System (SRS) Deactivation and Reactivation in this section.
3. WARNING: To reduce the risk of serious personal injury, read and follow all
warnings, cautions, notes and instructions in the steering wheel removal and installation
procedure.
Remove the steering wheel assembly. For additional information, refer to Wheel in this section.
4. Twist off the cap from the ignition switch cylinder.
5. NOTE: The lock cylinder is repaired by discarding the inoperative lock cylinder and building a
new lock cylinder using the appropriate lock repair package (F85Z-11582- AA). The lock repair
package includes a detailed instruction sheet to build the new lock cylinder to the current key
code of the vehicle.
SECTION 501-
14A: Handles, Locks, Latches and Mechanisms 2003 Mustang Workshop Manual Klj . 1 ba
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z
Is the resistance less than 5 ohms? E9 CHECK THE HORN FOR NORMAL OPERATION
z
Depress the steering wheel horn switch.
z Did the horn sound? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REFER to Section 413 -
06 .
E10 CHECK CIRCUIT 1032 (WH/BK) FOR SHORT TO POWER
z
Disconnect: Parking Lamp Relay.
z Disconnect: GEM C201e.
z Measure the voltage between GEM C201e Pin 11, Circuit
1032 (WH/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
E11 .
No
REPAIR Circuit 1032
(WH/BK). REPEAT the
self- test. CLEAR the
DTCs. E11 CHECK CIRCUIT 1032 (WH/BK) FOR SHORT TO GROUND
z
Measure the resistance between GEM C201e Pin 11, Circuit
1032 (WH/BK), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
E12 .
No
REPAIR Circuit 1032
(WH/BK). REPEAT the
self- test. CLEAR the
DTCs. E12 CHECK CIRCUIT 1032 (WH/BK) FOR OPEN
z
Measure the resistance between GEM C201e Pin 11, Circuit Yes Klj . 20 ba
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To deplete the backup power supply energy, disconnect the battery ground cable and
wait at least one minute. Be sure to disconnect auxiliary batteries and power supplies (if
equipped).
Disconnect the battery ground cable. For additional information, refer to
Section 414 - 01 .
2. Wait at least one minute for the backup power supply in the restraints control module (RCM) to deplete its stored energy.
3. 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.
WARNING: Do not set an air bag module down with the trim cover face down. This
will reduce the risk of injury in the event of an accidental deployment.
Remove the driver air bag module from the vehicle. Refer to Driver Air Bag Module in this
section.
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.
Connect a restraint system diagnostic tool to the vehicle harness at the top of the steering
column.
5. Disconnect the passenger air bag module electrical connector.
6. 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.
Connect a restraint system diagnostic tool to the vehicle harness.
7. Reconnect the battery ground cable. For additional information, refer to Section 414 - 01 .
Reactivation Procedure 1. WARNING: The restraint system diagnostic tool 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.
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.
Disconnect the battery ground cable. Refer to Section 414 - 01 .
2. Wait at least one minute for the backup power supply in the restraints control module (RCM) to deplete its stored energy.
3. Remove the restraint system diagnostic tool from the vehicle harness connector at the top of the Klj . 3 ba
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NOTE:
If a seat equipped with a seat mounted side air bag and/or a safety belt pretensioner (if
equipped) system is being serviced, the air bag system must be deactivated.
NOTE: Restraint system diagnostic tools MUST be installed under the seats in the seat side air bag (if
equipped) and safety belt pretensioner (if equipped) to floor connectors.
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.
To deplete the backup power supply energy, disconnect the battery ground cable and
wait at least one minute. Be sure to disconnect auxiliary batteries and power supplies (if
equipped).
Disconnect the battery ground cable and wait at least one minute. For additional information,
refer to Section 414 - 01 .
2. Remove the steering column opening lower finish panel. 1. Remove the screws.
2. Pull out to release the retaining clips and remove the steering column opening lower finish panel.
3. Remove the steering column opening lower reinforcement. 1. Remove the bolts.
2. Remove the steering column opening lower reinforcement. Klj . 2 ba
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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.
To deplete the backup power supply energy, disconnect the battery ground cable
and wait at least one minute. Be sure to disconnect auxiliary batteries and power
supplies (if equipped).
Disconnect the battery ground cable (14301) and wait at least one minute. For additional
information, refer to Section 414 - 01 .
2. WARNING: To reduce the risk of serious personal injury, read and follow all
warnings, cautions, notes, and instructions in the supplemental restraint system
(SRS) deactivation/reactivation procedure.
Deactivate the supplemental restraint system (SRS). For additional information, refer to
Supplemental Restraint System (SRS) Deactivation and Reactivation in the General
Procedures portion of this section.
2. Remove the two steering wheel plugs.
3. Remove the two driver air bag module retaining bolts (one shown).
4. Remove the driver air bag module. 1. Disconnect the driver air bag module electrical connector.
2. Remove the driver air bag module. Klj . 2 ba
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