ignition FORD MUSTANG 2003 Workshop Manual

Symptom Chart
Pinpoint Tests
CAUTION: Before removing and installing the GEM or its connectors, disconnect the Output Circuit Failure
B2488 RF Side Repeater Lamp
Output Circuit Failure GEM REFER to
Section 417 - 01 .
C1189 Brake Fluid Level Sensor
Input Short Circuit to Ground GEM REFER to
Section 413 - 01 .
C1223 Lamp Brake Warning
Output Circuit Failure GEM REFER to
Section 413 - 01 .
C1225 Lamp Brake Warning
Output Circuit Short to
Battery GEM REFER to
Section 413 - 01 .
Symptom Chart Condition
Possible Sources Action
z No communication with the generic
electronic module z
CJB Fuse 39
(5A)
z GEM.
z Circuitry. z
GO to
Pinpoint Test A .
z The courtesy lamps are inoperative zCJB Fuse 7
(20A).
z Door ajar switch
(es).
z Courtesy lamp
assemblies.
z Circuitry.
z GEM.
z Ignition Switch.
z Headlamp
Switch. z
GO to
Pinpoint Test B .
z The demand lighting is inoperative zCJB Fuse 7
(20A).
z Circuitry.
z GEM.
z Door ajar switch
(es).
z Demand lamp
assemblies.
z Ignition Switch.
z Headlamp
Switch. z
GO to
Pinpoint Test C .
z The illuminated entry is inoperative
when using the remote transmitter z
Remote
transmitter.
z GEM. z
GO to
Pinpoint Test D .
z The battery saver does not
deactivate after timeout z
Circuitry.
z GEM. z
GO to
Pinpoint Test E . Klj . 5 ba
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PINPOINT TEST B: THE COURTESY LAMPS ARE INOPERATIVE z
Is the resistance less than 5 ohms? A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
z
Measure the voltage between GEM C201b pin 2, circuit 397
(BK/WH), harness side and ground.
z Is any voltage present? Yes
REPAIR the circuit. TEST
the system for normal
operation.
No
REFER to
Section 418 - 00 .
Test Step Result / Action to Take
B1 CHECK IGNITION STATES
z
Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and IGN_R
while cycling the ignition switch through the OFF, ACC, RUN,
START and key out positions.
z Do the PID values agree with the ignition switch
positions? Yes
GO to
B2 .
No
For key- in-ignition
concerns, REFER to
Section 413 - 09 .
B2 CHECK THE DOOR AJAR INPUT TO THE GEM
z
Monitor the GEM PID D_DOOR, and P_DOOR, while
opening and closing the driver and passenger doors.
z Do the GEM PIDS D_DOOR and P_DOOR agree with the
driver and passenger door positions? Yes
GO to
B3 .
No
REFER to Section 413 -
09 .
B3 CHECK THE DOME LAMP SWITCH STATUS INPUT TO THE
GEM — MONITOR THE GEM PID DOMESW z
Monitor the GEM PID DOMESW, while activating, and
deactivating the dome lamp switch.
z Does the GEM PID DOMESW agree with the dome lamp
switch position? Yes
GO to
B4 .
No
GO to B13 .
B4 CHECK THE LUGGAGE COMPARTMENT LID AJAR INPUT
TO THE GEM — MONITOR THE GEM PID DECKLID Klj . 7 ba
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PINPOINT TEST C: THE DEMAND LIGHTING IS INOPERATIVE z
Is the resistance less than 5 ohms? CLEAR the DTCs.
B21 CHECK GROUND CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between luggage compartment lid
switch C430 Pin 1, Circuit 1205 (BK), harness side and
ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new luggage
compartment solenoid.
For additional information,
REFER to
Section 501 -
14A . REPEAT the self-
test. CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. Test Step Result / Action to Take
C1 CHECK GEM SUPPLIED POWER TO THE DEMAND LAMPS
z
Turn on both map lamps by depressing the map lamp
switches.
z Turn on both vanity mirror lamps.
z Open the luggage compartment lid.
z Do any of the lamps illuminate? Yes
GO to
C8 .
No
GO to C2 .
C2 CHECK IGNITION STATES
z
Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and IGN_R
while cycling the ignition switch through the OFF, ACC, RUN,
START and key out positions.
z Do the PID values agree with the ignition switch
positions? Yes
GO to
C3 .
No
For key- in-ignition
concerns, REFER to
Section 413 - 09 .
C3 CHECK DRIVER AND PASSENGER DOOR AJAR INPUTS TO
THE GEM z
Monitor the GEM PIDs D_DOOR and P_DOOR, while
opening and closing the driver and passenger doors.
z Did the GEM PIDs D_DOOR and P_DOOR agree with the
driver and passenger door positions? Yes
GO to
C4 .
No
REFER to Section 413 -
09 . Klj . 12 ba
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PINPOINT TEST D: THE ILLUMINATED ENTRY IS INOPERATIVE
WHEN USING THE REMOTE TRANSMITTER (coupe), map C907 (convertible), right hand vanity C906, left
hand vanity C978, or luggage compartment C4111.
z Measure the voltage between inoperative demand lamp,
Circuit 705 (LG/OG), harness side and ground.
z Is the voltage greater than 10 volts? No
REPAIR the circuit in
question. REPEAT the
self-
test. CLEAR the
DTCs. C9 CHECK CIRCUIT 1205 (BK) FOR OPEN AT INOPERATIVE
DEMAND LAMP z
Measure the resistance between inoperative demand lamp
Circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new demand
lamp assembly. REPEAT
the self-
test. CLEAR the
DTCs.
No
REPAIR the circuit in
question. REPEAT the
self- test. CLEAR the
DTCs. Test Step Result / Action to Take
D1 CHECK THE REMOTE TRANSMITTER
INPUT TO THE GEM z
Remove the ignition key from the ignition.
z Depress the lock and then the unlock
buttons on the remote transmitter.
z Do the doors lock when the lock button
is depressed and unlock when the
unlock button is depressed? Yes
GO to
D2 .
No
REFER to Section 501 - 14B .
D2 CHECK OPERATION OF ILLUMINATED
ENTRY WITHOUT REMOTE TRANSMITTER z
Open the driver door.
z Do the courtesy lamps illuminate? Yes
INSTALL a new GEM. For additional
information, REFER to
Section 419 - 10 .
REPEAT the self- test. CLEAR the DTCs.
No
GO to Pinpoint Test B . Klj . 14 ba
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DIAGNOSIS AND TESTING
Daytime Running Lamps (DRL)
Refer to Wiring Diagrams Cell
97 , Daytime Running Lamps for schematic and connector information.
Principles of Operation
Daytime Running Lamps (DRL)
The daytime running lamps (DRL) system operates the low beam headlamps at a reduced intensity.
The DRL module (15A270) supplies pulse width modulated (PWM) voltage, approximately 75%- 92%
of battery voltage, to the low beam headlamps when the following conditions are met:
zThe parking brake control is released.
z The high beam headlamps are disabled.
z The ignition switch (11572) is in the RUN position.
The DRL module remains enabled when the low beam headlamps are turned on.
Inspection and Verification 1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. Verify the headlamps are operating correctly. Correct any concerns before proceeding to the
SECTION 417-
04: Daytime Running Lamps 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged DRL module
z Damaged parking brake signal switch and
bracket (15A851) z
Blown battery junction box (BJB) Maxi-
Fuse FOG+DRL (20A)
z Damaged wiring harness
z Loose or corroded connection
z Damaged DRL module
z Damaged parking brake signal switch and
bracket Klj . 1 ba
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next step. For additional information, refer to
Section 417 - 01 .
4. Verify the parking brake control is fully released.
5. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
6. If the concern is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart
Pinpoint Tests
PINPOINT TEST A: THE DAYTIME RUNNING LAMPS ARE
INOPERATIVE Symptom Chart Condition
Possible Sources Action
z The daytime running lamps are
inoperative z
BJB Maxi- Fuse
FOG+DRL (20A).
z Circuitry.
z Parking brake
signal switch and
bracket.
z DRL module. z
GO to
Pinpoint Test A .
z The daytime running lamps are
on with the parking brake set z
Circuitry.
z Parking brake
signal switch and
bracket.
z DRL module. z
GO to
Pinpoint Test B .
z The daytime running lamps are
on with the ignition switch off z
Circuitry.
z Ignition switch.
z DRL module. z
GO to
Pinpoint Test C .
z The low beam headlamps are on
at full intensity in DRL mode z
Circuitry.
z Headlamp switch.
z DRL module. z
GO to
Pinpoint Test D .
z The low beam headlamps are on
at reduced intensity with the
headlamp switch on z
Circuitry.
z Headlamp switch. z
REFER to
Section 417 -
01 .
Test Step Result / Action to Take
A1 CHECK THE PARKING BRAKE SWITCH SIGNAL
CIRCUIT TO THE DRL MODULE FOR SHORT TO GROUND NOTE:
Verify the parking brake control is fully released
for this step.
z Key in OFF position.
z Disconnect: DRL Module C1030.
z Measure the resistance between DRL module C1030 Pin
6, Circuit 22 (LB/BK), harness side and ground. Yes
GO to
A3 .
No
GO to A2 . Klj . 2 ba
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z
Is the resistance greater than 10,000 ohms? A2 CHECK THE PARKING BRAKE SWITCH
z
Disconnect: Parking Brake Switch C306.
z Measure the resistance between DRL module C1030 Pin
6, Circuit 22 (LB/BK), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
INSTALL a new parking brake
signal switch and bracket.
TEST the system for normal
operation.
No
REPAIR the circuit. TEST the
system for normal operation.
A3 CHECK VOLTAGE TO THE DRL MODULE
z
Measure the voltage between DRL module C1030 Pin 2,
Circuit 477 (LB/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A4 .
No
REPAIR the circuit. TEST the
system for normal operation. A4 CHECK IGNITION SENSE INPUT
z
Key in ON position.
z Measure the voltage between DRL module C1030 Pin 3,
Circuit 298 (VT/OG), harness side and ground. Yes
GO to
A5 .
No
REPAIR the circuit. TEST the
system for normal operation. Klj . 3 ba
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PINPOINT TEST C: THE DAYTIME RUNNING LAMPS ARE ON WITH
THE IGNITION SWITCH OFF z
Do the DRL turn off? B2 CHECK THE PARKING BRAKE SWITCH SIGNAL CIRCUIT
z
Key in OFF position.
z Disconnect: DRL Module C1030.
z Measure the resistance between parking brake switch C306,
Circuit 22 (LB/BK), harness side and DRL module C1030 Pin
6, Circuit 22 (LB/BK), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new DRL
module. REFER to
Module
— Daytime
Running Lamps (DRL) .
TEST the system for
normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE IGNITION SWITCH INPUT TO THE DRL
MODULE FOR VOLTAGE z
Key in OFF position.
z Disconnect: DRL Module C1030.
z Measure the voltage between DRL module C1030 Pin 3,
Circuit 298 (VT/OG), harness side and ground.
z Is voltage indicated? Yes
GO to
C2 .
No
INSTALL a new DRL module.
REFER to Module — Daytime
Running Lamps (DRL) . TEST
the system for normal
operation. C2 CHECK THE IGNITION SWITCH
z
Check the ignition switch; refer to the Wiring Diagrams
Cell 149.
z Is the ignition switch OK? Yes
REPAIR Circuit 298 (VT/OG)
for short to battery. TEST the
system for normal operation.
No
INSTALL a new ignition switch.
REFER to
Section 211 - 05 .
TEST the system for normal
operation. Klj . 5 ba
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The generic electronic module (GEM) is on the ISO 9141 network. The GEM module controls a variety
of systems including one touch down windows, wipers, perimeter anti-
theft, and warning chimes. For
additional information, refer to Section 419 - 10 .
The anti- lock brake control module communicates over the ISO 9141 communication network when
not equipped with traction control and communicates over the SCP communication network when it is
equipped with the traction control option. The anti- lock brake control module controls the brake
pressure to the four wheels to keep the vehicle under control while braking. For additional information
on anti- lock brake control module without traction control, refer to Section 206 - 09A . For additional
information on anti- lock brake control module with traction control, refer to Section 206 - 09B .
The instrument cluster is on the SCP communication network. The instrument cluster displays driver
information. The instrument cluster incorporates the PATS control module functions. For additional
information on the PATS system, refer to Section 419 - 01 . For additional information on the instrument
cluster, refer to Section 413 - 01 .
Inspection and Verification 1. Verify the customer concern.
2. Visually inspect for obvious signs of electrical damage.
3. If the concern remains after the inspection, connect diagnostic tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from diagnostic
tool menu. If diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check that the correct version of the program card is installed.
z check the connections to the vehicle.
z check the ignition switch position.
If the diagnostic tool still does not communicate with the vehicle, go to Pinpoint Test H. 4. Go to Pinpoint Test PC.
System Precheck Visual Inspection Chart Electrical
z
Central junction box (CJB) Fuse 31 (5A)
z Damaged wiring harness
z Loose or corroded connections
z Anti- lock brake control module without traction control (optional)
z Anti- lock brake control module with traction control (optional)
z Generic electronic module (GEM)
z Restraint control module (RCM)
z Powertrain control module (PCM)
z Instrument cluster Klj . 2 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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