2003 FORD MUSTANG engine

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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PINPOINT TEST G: THE ANTI - THEFT SYSTEM DOES NOT OPERATE Test Step Result / Action to Take
NOTE:
Large metallic objects, electronic debit transponder devices or a second key on the same
key ring as the PATS ignition key may cause vehicle starting problems and record DTCs under
certain conditions. If a fault cannot be identified, examine the customer's key for such objects or
devices. If present, inform the customer that they need to keep these objects from touching the
PATS ignition key while starting the engine. These objects and devices cannot damage the
PATS ignition key, but can cause a momentary problem if they are too close to the key during
engine start. If a problem occurs, turn ignition OFF and restart the engine with all other objects
on the key ring held away from the ignition key. Check to ensure the encoded ignition key used
by the customer is an approved Ford encoded ignition key (encoded ignition keys from Rotunda,
Ilco, Curtis, or Strattec are approved Ford encoded ignition keys). F1 USE THE DTCS FROM THE INSTRUMENT
CLUSTER SELF- TESTS z
Use the recorded results from the Instrument
Cluster Continuous and On- Demand Self-Tests.
z Is DTC B1600 retrieved? Yes
GO to
F2 .
No
If other DTCs are retrieved, REFER
to Instrument Cluster Diagnostic
Trouble Code (DTC) Index.
If no DTCs are retrieved, system is
OK. F2 PROGRAM A NEW ENCODED IGNITION KEY
z
Key in OFF position.
z NOTE: Check to make sure the customer and
replacement encoded ignition keys are approved
Ford encoded PATS ignition keys. Unapproved
PATS keys do not always operate correctly over
different temperature ranges (encoded ignition
keys from Rotunda, Ilco, or Strattec are approved
encoded ignition keys).
z Cut a new encoded ignition key.
z Key in ON position.
z Program the new encoded ignition key; for
additional information, refer to Key Programming — Erase All Key Codes and Program
Two Keys .
z Enter the following diagnostic mode on the
diagnostic tool: Instrument Cluster On- Demand
Self- Test.
z Is DTC B1600 still present? Yes
GO to
F3 .
No
If no other DTCs are retrieved,
system is OK.
If other DTCs are retrieved, REFER
to Instrument Cluster Diagnostic
Trouble Code (DTC) Index. F3 INSTALL A NEW PATS TRANSCEIVER
z
Key in OFF position.
z Install a new PATS transceiver; for additional
information, refer to Module — Passive Anti - Theft
Transceiver .
z Key in ON position.
z NOTE: Use the customer's original encoded
ignition key, not the encoded ignition key that was
cut in the previous step.
z Enter the following diagnostic mode on the
diagnostic tool: Instrument Cluster On- Demand
Self- Test.
z Is DTC B1600 retrieved? Yes
INSTALL a new instrument cluster;
for additional information, REFER to
Section 413
- 01 . CYCLE the ignition
to RUN using two encoded ignition
keys. Go To Pinpoint Test J to
initialize the module. REPEAT the
self- test. CLEAR the DTCs.
No
System is OK. Klj . 9 ba
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CORRECTLY —
PATS RECEIVED INCORRECT KEY- CODE FROM
IGNITION KEY TRANSPONDER (UNPROGRAMMED ENCODED
IGNITION KEY) Test Step Result / Action to Take
NOTE:
Large metallic objects, electronic debit transponder devices or a second key on the same
key ring as the PATS ignition key may cause vehicle starting problems and record DTCs under
certain conditions. If a fault cannot be identified, examine the customer's key for such objects or
devices. If present, inform the customer that they need to keep these objects from touching the
PATS ignition key while starting the engine. These objects and devices cannot damage the
PATS ignition key, but can cause a momentary problem if they are too close to the key during
engine start. If a problem occurs, turn ignition OFF and restart the engine with all other objects
on the key ring held away from the ignition key. Check to ensure the encoded ignition key used
by the customer is an approved Ford encoded ignition key (encoded ignition keys from Rotunda,
Ilco, Curtis, or Strattec are approved Ford encoded ignition keys). G1 USE THE DTCS FROM THE
INSTRUMENT CLUSTER SELF TESTS z
Use the recorded results from the
Instrument Cluster Continuous
and On- Demand Self- Tests.
z Is DTC B1601 recorded? Yes
GO to
G2 .
No
System is OK. CHECK all customer encoded ignition
keys with Instrument Cluster On- Demand Self-Test to
verify all other encoded ignition keys are programmed. G2 CHECK FOR PROGRAMMED
ENCODED IGNITION KEYS —
MONITOR THE INSTRUMENT
CLUSTER PID NUMKEYS z
Monitor the instrument cluster
PID NUMKEYS.
z Does the instrument cluster
PID NUMKEYS display 8? Yes
ERASE and REPROGRAM the key codes; for
additional information, REFER to
Key Programming —
Erase All Key Codes and Program Two Keys .
REPEAT the self- test. CLEAR the DTCs.
No
GO to G3 .
G3 CHECK THE NUMBER OF
PROGRAMMED ENCODED IGNITION
KEYS AVAILABLE z
Verify there are at least two
currently programmed encoded
ignition keys available with the
vehicle.
z Are at least two currently
programmed encoded ignition
keys available with the vehicle? Yes
GO to
G4 .
No
CUT a new encoded ignition keys so that at least two
encoded ignition keys are available. PROGRAM the
encoded ignition keys; Key Programming — Erase All
Key Codes and Program Two Keys . GO to
G4 .
G4 VERIFY THE INSTRUMENT
CLUSTER PID SPARE_KY INDICATES
ENABLE z
Monitor the instrument cluster
PID SPARE_KY.
z Does the instrument cluster
PID SPARE_KY indicate
ENABLE? Yes
REFER to
Key Programming — Erase All Key Codes
and Program Two Keys . CLEAR the DTCs, REPEAT
the self- testGO to G5 .
No
REFER to Key Programming — Enable/Disable Spare Klj . 10 ba
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PINPOINT TEST H: THE ANTI-
THEFT SYSTEM DOES NOT OPERATE
CORRECTLY — PATS RECEIVED INVALID FORMAT OF KEY- CODE
FROM IGNITION KEY TRANSPONDER (PARTIAL KEY READ) Key Programming to enable the PID SPARE KEY to
ENABLE. TEST the system for normal operation.
Once completed, GO to G5 .
G5 CHECK THE ENCODED IGNITION
KEYS FOR CORRECT OPERATION z
Key in OFF position.
z Key in ON position.
z Start the vehicle using the first
encoded ignition key.
z Key in ON position.
z Start the vehicle with the second
ignition key.
z Key in OFF position.
z Does the vehicle start correctly
using both encoded ignition
keys? Yes
System is OK. If there are additional keys that need to
be programmed, for additional information, REFER to
Key Programming
— Program a Key Using Two
Programmed Keys .
No
GO to G6 .
G6 RETRIEVE THE INSTRUMENT
CLUSTER DTCS — CHECK FOR DTC
B1601 z
Retrieve and document
continuous DTCs.
z Enter the following diagnostic
mode on the diagnostic tool:
Clear Continuous DTCs.
z Carry out a instrument cluster
self- test using both ignition keys
from Step G5.
z Is DTC B1601 retrieved? Yes
INSTALL a new instrument cluster; for additional
information, REFER to
Section 413 - 01 . CYCLE the
ignition to RUN using two encoded ignition keys. GO
to Pinpoint Test J to initialize the vehicle. REPEAT the
self- test. CLEAR the DTCs.
No
System is OK.
If other DTCs are retrieved, REFER to Instrument
Cluster Module Diagnostic Trouble Code (DTC) Index. Test Step Result / Action to Take
NOTE:
Large metallic objects, electronic debit transponder devices or a second key on the same
key ring as the PATS ignition key may cause vehicle starting problems and record DTCs under
certain conditions. If a fault cannot be identified, examine the customer's key for such objects or
devices. If present, inform the customer that they need to keep these objects from touching the
PATS ignition key while starting the engine. These objects and devices cannot damage the
PATS ignition key, but can cause a momentary problem if they are too close to the key during
engine start. If a problem occurs, turn ignition OFF and restart the engine with all other objects
on the key ring held away from the ignition key. Check to ensure the encoded ignition key used
by the customer is an approved Ford encoded ignition key (encoded ignition keys from Rotunda,
Ilco, Curtis, or Strattec are approved Ford encoded ignition keys). H1 USE THE DTCS FROM THE
INSTRUMENT CLUSTER SELF TESTS z
Use the recorded results from the
Instrument Cluster Continuous and
On- Demand Self- Tests.
z Is DTC B1602 retrieved? Yes
GO to
H2 .
No
System is OK. CHECK all customer encoded
ignition keys with Instrument Cluster On- Demand
Self- Test to verify all other keys are programmed. Klj . 11 ba
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GENERAL PROCEDURES
Key Programming —
Additional Key With One Programmed
Key
NOTE: This procedure is used when a customer needs to have an additional key programmed into the
vehicle without erasing stored key codes, but does not have two programmed keys available. This
procedure is also useful when attempting to determine if an ignition key is defective, as a new key can
be installed without erasing keys or without having two programmed keys available.
NOTE: Before programming, the new key must have the correct mechanical cut for the ignition lock.
NOTE: If eight keys are already programmed, this procedure will not allow any further ignition keys to
be programmed without erasing all stored key codes first. The number of keys programmed into the
system can be determined using the PID NUMKEYS.
1. Turn the ignition switch from the OFF position to the RUN position using the new, unprogrammed ignition key.
2. Enter diagnostic tool using the Ford Service Function (FSF) card and enter the appropriate instrument cluster. Follow Security Access to obtain security access. For additional information,
refer to Security Access — Procedure .
3. From the diagnostic tool menu Select: IGNITION KEY CODE PROGRAM.
4. Turn the ignition switch to the OFF position and disconnect diagnostic tool.
5. Attempt to start the engine with the new ignition key. The vehicle engine should start and run normally.
SECTION 419-
01: Anti-Theft — PATS 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool Klj . 1 ba
22003 Mustang Workshop Manual
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Component Tests
Grid Wire Test
1. Using a bright lamp inside the vehicle, inspect the wire grid from the exterior. A broken grid wire will appear as a brown spot.
2. Run the engine at idle. Set the rear window defrost switch to ON. The indicator light should come on.
3. Working from the interior of the vehicle with a voltmeter, contact the broad red- brown stripes of
the rear glass window positive lead to battery side and negative lead to ground side. The meter
should read 10- 13 volts. A lower voltage reading indicates a loose ground connection.
4. Contact a good ground point with the negative lead of the meter. The voltage reading should not differ.
5. With the negative lead of the meter grounded, touch each grid line of the heated rear window glass at its midpoint with the positive lead. A reading of approximately 6 volts indicates that the
line is good. A reading of zero volts indicates that the line is broken between the midpoint and
the B+ side of the grid line. A reading of 12 volts indicates that the circuit is broken between the
midpoint of the grid line and ground. z
Is the voltage greater than 10 volts? I4 CHECK THE ICM FOR CORRECT OPERATION
z
Disconnect all ICM connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all ICM 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 ICM. REFER
to Section 413
- 01 . CLEAR the
DTCs. REPEAT the self-test.
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. Klj . 31 ba
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REMOVAL AND INSTALLATION
Rear Bumper
Removal and Installation
All vehicles
1. Remove the rear bumper cover. For additional information, refer to Rear Bumper Cover in this
section.
2. Remove the rear bumper cover isolator.
Vehicles with 4.6L engines
3. Remove the bolts and the exhaust outlet pipe bumper bracket.
All vehicles 4. Remove the rear bumper brace and tongue bolts.
5. Remove the bolts and the rear bumper.
SECTION 501-
19: Bumpers 2003 Mustang Workshop Manual Klj . 1 ba
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