key FORD MUSTANG 2003 Workshop Manual

Test Step Result / Action to Take
F1 CHECK CIRCUIT 70 (LB/WH) FOR OPEN
z
Key in OFF position.
z Inspect the DLC C251 Pin 7, Circuit 70 (LB/WH) for
damage, repair as necessary.
z Disconnect: GEM C201e.
z Measure the resistance between GEM C201e Pin 6,
Circuit 70 (LB/WH), harness side and DLC C251 Pin 7,
Circuit 70 (LB/WH), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
F2 .
No
REPAIR Circuit 70 (LB/WH)
between the GEM C201e and
DLC C251. TEST the system
for normal operation. F2 CHECK FOR SHORT TO GROUND AND POWER AT
DLC C251 — GEM C201e DISCONNECTED z
Key in ON position.
z Measure the voltage between DLC C251 Pin 7, Circuit 70
(LB/WH), harness side and C251 Pin 4, Circuit 1205
(BK); and between DLC C251 Pin 7, Circuit 70 (LB/WH),
harness side and C251 Pin 16, Circuit 1047 (LG/RD),
harness side.
z Is the voltage indicated in either measurement zero
volts? Yes
CONNECT the GEM module
C201e. GO to
F3 .
No
INSTALL a new GEM. For
additional information, REFER
to Section 419 - 10 . TEST the
system for normal operation. F3 CHECK FOR SHORT TO GROUND AND POWER AT
DLC C251 — IN-LINE C314 DISCONNECTED z
Key in OFF position.
z Disconnect: In- Line C314.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 7, Circuit 70
(LB/WH), harness side and C251 Pin 4, Circuit 1205
(BK); and between DLC C251 Pin 7, Circuit 70 (LB/WH),
harness side and C251 Pin 16, Circuit 1047 (LG/RD),
harness side. Yes
GO to
F4 .
No
GO to F5 . Klj . 12 ba
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z
Is the voltage indicated in either measurement zero
volts? F4 CHECK FOR SHORT TO GROUND AND POWER AT
DLC C251 — RCM C2041 DISCONNECTED z
Key in OFF position.
z Deactivate the air bag system; REFER to Section 501 -
20B .
z Disconnect: RCM C2041.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 7, Circuit 70
(LB/WH), harness side and C251 Pin 4, Circuit 1205
(BK); and between DLC C251 Pin 7, Circuit 70 (LB/WH),
harness side and C251 Pin 16, Circuit 1047 (LG/RD),
harness side.
z Is the voltage indicated in either measurement zero
volts? Yes
REPAIR Circuit 70 (LB/WH)
between DLC C251, GEM
C201e, RCM C2041, and in-
line C314. TEST the system
for normal operation.
No
INSTALL a new RCM. REFER
to
Section 501 - 20B . TEST the
system for normal operation. F5 CHECK FOR THE ANTI-
LOCK BRAKE CONTROL
MODULE z
Key in OFF position.
z Connect: In- Line C3141.
z Check the vehicle for any version of the anti- lock brake
control module.
z Is the vehicle equipped with any version of the anti-
lock brake control module (with or without traction
control)? Yes
GO to
F6 .
No
GO to F7 .
F6 CHECK FOR SHORT TO GROUND AND POWER AT
DLC C251 — ANTI-LOCK BRAKE CONTROL MODULE C135
DISCONNECTED z
Disconnect: Anti- Lock Brake Control Module C135.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 7, Circuit 70
(LB/WH), harness side and C251 Pin 4, Circuit 1205
(BK); and between DLC C251 Pin 7, Circuit 70 (LB/WH),
harness side and C251 Pin 16, Circuit 1047 (LG/RD),
harness side. Yes
GO to
F7 .
No
INSTALL a new anti- lock brake
control module. For additional
information on the anti- lock
brake control module without
traction control, REFER to Klj . 13 ba
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PINPOINT TEST G: NO MODULE/NETWORK COMMUNICATION —
SCP NETWORK z
Is the voltage indicated in either measurement zero
volts? Section 206 - 09A . For
additional information on the
anti- lock brake control module
with traction control, REFER to
Section 206 - 09B . TEST the
system for normal operation. F7 CHECK FOR SHORT TO GROUND AND POWER AT
DLC C251 — IN-LINE C140 DISCONNECTED z
Key in OFF position.
z Disconnect: In- Line C140.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 7, Circuit 70
(LB/WH), harness side and C251 Pin 4, Circuit 1205
(BK); and between DLC C251 Pin 7, Circuit 70 (LB/WH),
harness side and C251 Pin 16, Circuit 1047 (LG/RD),
harness side.
z Is the voltage indicated in either measurement zero
volts? Yes
REPAIR Circuit 70 (LB/WH)
between in-
line C314 and in-
line C140. TEST the system
for normal operation.
No
REPAIR Circuit 70 (LB/WH)
between in- line C140 and the
anti-lock brake control module
C135. TEST the system for
normal operation. Test Step Result / Action to Take
G1 CHECK DIAGNOSTIC TOOL PINS FOR DAMAGE
z
Inspect diagnostic tool pins for damage.
z Are the diagnostic tool pins OK? Yes
GO to
G2 .
No
REPAIR the diagnostic tool
terminals. TEST the system for
normal operation. Klj . 14 ba
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G2 CHECK DLC C251 PINS 2 AND 10 FOR DAMAGE
z
Key in OFF position.
z Inspect the DLC C251 pins for damage.
z Are the pins OK? Yes
GO to
G3 .
No
REPAIR the DLC C251. TEST
the system for normal operation. G3 CHECK THE VEHICLE FOR THE ANTI-
LOCK BRAKE
CONTROL MODULE z
Check the vehicle for any version of the anti- lock brake
control module.
z Is the vehicle equipped with any version of the anti-
lock brake control module (with or without traction
control)? Yes
GO to
G4 .
No
GO to G7 .
G4 CHECK CIRCUIT 914 (TN/OG) AND CIRCUIT 915
(PK/LB) FOR OPEN — ANTI-LOCK BRAKE CONTROL
MODULE C135 DISCONNECTED z
Disconnect: Anti- Lock Brake Control Module C135.
z Measure the resistance between anti- lock brake control
module C135 Pin 30, Circuit 914 (TN/OG), harness
side and DLC C251 Pin 2, Circuit 914 (TN/OG),
harness side.
z Measure the resistance between anti- lock brake control
module C135 Pin 29, Circuit 915 (PK/LB), harness side
and DLC C251 Pin 10, Circuit 915 (PK/LB), harness
side.
z Are the resistances less than 5 ohms? Yes
GO to
G5 .
No
REPAIR the circuit(s) in question
between in- line C215 and DLC
C251. For additional information,
REFER to Communication Circuit Wiring Repair . TEST the
system for normal operation. G5 CHECK CIRCUIT 914 (TN/OG) AND CIRCUIT 915 Klj . 15 ba
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(PK/LB) FOR THE SOURCE OF THE CONCERN — ANTI-
LOCK BRAKE CONTROL MODULE C135 DISCONNECTED z
Key in ON position.
z Measure the voltage between DLC C251 Pin 2, Circuit
914 (TN/OG), harness side and C251 Pin 4, Circuit
1205 (BK); and between DLC C251 Pin 2, Circuit 914
(TN/OG), harness side and C251 Pin 16, Circuit 1047
(LG/RD), harness side.
z Measure the voltage between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 4,
Circuit 1205 (BK); and between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 16,
Circuit 1047 (LG/RD), harness side.
z Is the voltage zero volts for any measurement? Yes
GO to
G6 .
No
INSTALL a new anti- lock brake
control module. For additional
information on the anti- lock brake
control module without traction
control, REFER to Section 206 -
09A . For additional information
on the anti- lock brake control
module with traction control,
REFER to Section 206 - 09B .
TEST the system for normal
operation. G6 CHECK CIRCUIT 914 (TN/OG) AND CIRCUIT 915
(PK/LB) FOR THE SOURCE OF THE CONCERN — IN-LINE
C144 DISCONNECTED z
Key in OFF position.
z Disconnect: In- Line C144.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 2, Circuit
914 (TN/OG), harness side and C251 Pin 4, Circuit
1205 (BK); and between DLC C251 Pin 2, Circuit 914
(TN/OG), harness side and C251 Pin 16, Circuit 1047
(LG/RD), harness side.
z Measure the voltage between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 4, Yes
GO to
G8 .
No
REPAIR the circuit(s) in question
between in- line C144 and the
anti- lock brake control module
C135. REFER to Communication Circuit Wiring Repair . TEST the
system for normal operation. Klj . 16 ba
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Circuit 1205 (BK); and between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 16,
Circuit 1047 (LG/RD), harness side.
z Is the voltage zero volts for any measurement? G7 CHECK CIRCUIT 914 (TN/OG) AND CIRCUIT 915
(PK/LB) FOR OPEN — PCM C175 DISCONNECTED z
Disconnect: PCM C175.
z Measure the resistance between PCM C175 Pin 16,
Circuit 914 (TN/OG), harness side and DLC C251 Pin
2, Circuit 914 (TN/OG), harness side.
z Measure the resistance between PCM C175 Pin 15,
Circuit 915 (PK/LB), harness side and DLC C251 Pin
10, Circuit 915 (PK/LB), harness side.
z Are the resistances less than 5 ohms? Yes
GO to
G8 .
No
REPAIR the circuit(s) in question
between in- line C215 and DLC
C251. For additional information,
REFER to Communication Circuit Wiring Repair . TEST the
system for normal operation. G8 CHECK CIRCUIT 914 (TN/OG) AND CIRCUIT 915
(PK/LB) FOR THE SOURCE OF THE CONCERN — PCM
C175 DISCONNECTED z
Key in OFF position.
z Disconnect: PCM C175.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 2, Circuit
914 (TN/OG), harness side and C251 Pin 4, Circuit
1205 (BK); and between DLC C251 Pin 2, Circuit 914
(TN/OG), harness side and C251 Pin 16, Circuit 1047
(LG/RD), harness side. Yes
GO to
G9 .
No
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual Section 3 for
diagnosis and testing. Klj . 17 ba
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z
Measure the voltage between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 4,
Circuit 1205 (BK); and between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 16,
Circuit 1047 (LG/RD), harness side.
z Is the voltage zero volts for any measurement? G9 CHECK CIRCUIT 914 (TN/OG) AND CIRCUIT 915
(PK/LB) FOR THE SOURCE OF THE CONCERN — IN-LINE
C215 DISCONNECTED z
Key in OFF position.
z Disconnect: In- Line C215.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 2, Circuit
914 (TN/OG), harness side and C251 Pin 4, Circuit
1205 (BK); and between DLC C251 Pin 2, Circuit 914
(TN/OG), harness side and C251 Pin 16, Circuit 1047
(LG/RD), harness side.
z Measure the voltage between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 4,
Circuit 1205 (BK); and between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 16,
Circuit 1047 (LG/RD), harness side. Yes
GO to
G10 .
No
REPAIR the circuit(s) in question
between in- line C215, in - line
C144 (if equipped with the anti-
lock brake control module), and
the PCM C175. For additional
information, REFER to
Communication Circuit Wiring Repair . TEST the system for
normal operation. Klj . 18 ba
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PINPOINT TEST H: NO MODULE / NETWORK COMMUNICATION —
NO POWER TO THE DIAGNOSTIC TOOL z
Is the voltage zero volts for any measurement? G10 CHECK CIRCUIT 914 (TN/OG) AND CIRCUIT 915
(PK/LB) FOR THE SOURCE OF THE CONCERN —
INSTRUMENT CLUSTER C220a DISCONNECTED z
Key in OFF position.
z Disconnect: Instrument Cluster C220a.
z Key in ON position.
z Measure the voltage between DLC C251 Pin 2, Circuit
914 (TN/OG), harness side and C251 Pin 4, Circuit
1205 (BK); and between DLC C251 Pin 2, Circuit 914
(TN/OG), harness side and C251 Pin 16, Circuit 1047
(LG/RD), harness side.
z Measure the voltage between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 4,
Circuit 1205 (BK); and between DLC C251 Pin 10,
Circuit 915 (PK/LB), harness side and C251 Pin 16,
Circuit 1047 (LG/RD), harness side.
z Is the voltage zero volts for any measurement? Yes
REPAIR the circuit(s) in question
between in-
line C215, DLC
C251, and the instrument cluster
C220a. For additional
information, REFER to
Communication Circuit Wiring Repair . TEST the system for
normal operation.
No
INSTALL a new instrument
cluster. For additional
information, REFER to Section 413 - 01 . TEST the system for
normal operation. Test Step Result / Action to
Take Klj . 19 ba
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H1 CHECK DIAGNOSTIC TOOL PINS FOR DAMAGE
z
Inspect diagnostic tool pins.
z Are the pins OK? Yes
GO to
H2 .
No
REPAIR diagnostic
tool pins. TEST the
system for normal
operation. H2 CHECK DLC C251 FOR DAMAGE
z
Key in OFF position.
z Inspect the DLC C251 pins for damage.
z Are the pins OK? Yes
GO to
H3 .
No
REPAIR DLC C251.
TEST the system for
normal operation. H3 CHECK VOLTAGE TO DLC C251 PIN 16 —
CIRCUIT 1047 (LG/RD) z
Measure the voltage between DLC C251 Pin 16, Circuit 1047
(LG/RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
H4 .
No
REPAIR Circuit
1047 (LG/RD).
TEST the system for
normal operation. H4 CHECK THE DLC GROUND —
CIRCUIT 1205 (BK) AND CIRCUIT
651 (BK/YE) z
Measure the resistance between DLC C251 Pin 4, Circuit 1205
(BK), harness side and ground; and between DLC C251 Pin 5,
Circuit 651 (BK/YE), harness side and ground. Yes
CHECK diagnostic
tool. TEST the
system for normal
operation.
No
REPAIR the circuit
in question. TEST
the system for
normal operation. Klj . 20 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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