FORD MUSTANG 2003 Workshop Manual

SPECIFICATIONS
SECTION 418-
00: Module Communications Network 2003 Mustang Workshop Manual General Specifications
Item Specification
Heat shrink tube overlap mm (inch) 12.7 (0.5)
Wire insulation removal length (twist side) mm (inch) 37.2 (1.5)
Wire insulation removal length (receiving side) mm (inch) 19.5 (0.75)
Raychem SCT® Heat Shrink Tubing, Motorcraft part number WT-
5627 ESB-
M99D56-A2 Klj . 1 ba
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DESCRIPTION AND OPERATION
Communications Network
Module Communications Network
SECTION 418-
00: Module Communications Network 2003 Mustang Workshop Manual Item Part
Number Description
1 12A650 Powertrain Control Module (PCM)
2 — Restraint Control Module (RCM)
3 10849 Hybrid Electronic Cluster (HEC)
4 14B205 Generic Electronic Module (GEM)
5 2C219 Anti-
Lock Brake System / Traction Control
(ABS/TC) Module Klj . 1 ba
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Klj . 2 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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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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PINPOINT TEST PC: DATA LINK DIAGNOSTICS NETWORK TEST
Symptom Chart
Test Step Result / Action to Take
PC1 DATA LINK
DIAGNOSTICS NETWORK
TEST z
Run the Data Link
Diagnostics Network
Test.
z Is SYSTEM PASSED
obtained? Yes
Test PASSED. RETURN to the Symptom Chart of the section
for the module in question.
No
If no response from the diagnostic tool, GO to
Pinpoint Test H .
If CKT70=ALL ECUS NO RESP / NOT EQUIP, GO to Pinpoint Test F .
If CKT914 or CKT915=ALL ECUS NO RESP / NOT EQUIP,
GO to Pinpoint Test G .
If CKT70, CKT914, or CKT915=SOME ECUS NO RESP/NOT
EQUIP, REFER to Symptom Chart.
If the module in question is NO RESPONSE ON CKT914
(BUS+), or NO RESPONSE ON CKT915 (BUS-), REFER to
Symptom Chart.
If the module in question is NO RESPONSE/NOT EQUIPPED,
REFER to Symptom Chart.
Symptom Chart Condition
Possible Sources Action
z The module does not
respond to the diagnostic
tool — anti-lock brake control
module z
Wire or connection in SCP
communication network
(with traction control).
z Wire or connection in ISO
9141 communication
network (without traction
control).
z Anti- lock brake control
module without traction
control (optional).
z Anti- lock brake control
module with traction
control (optional). z
GO to
Pinpoint Test A .
z The module does not
respond to the diagnostic
tool — generic electronic
module (GEM) z
Wire or connection in ISO
9141 communication
network.
z GEM. z
GO to
Pinpoint Test B .
z The module does not
respond to the diagnostic
tool — restraint control
module (RCM) z
Wire or connection in ISO
9141 communication
network.
z RCM. z
GO to
Pinpoint Test C .
z The module does not
respond to the diagnostic z
Wire or connection in SCP
communication network. z
GO to
Pinpoint Klj . 3 ba
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Pinpoint Tests
CAUTION: Be careful when probing the CJB, battery junction box (BJB) or any
connectors. Damage will result to the connector receptacle if the probe or terminal being used
is too large.
CAUTION: Electronic modules are sensitive to static electrical charges. If exposed to
these charges, damage may result.
NOTE: If DTCs are recorded and the symptom is not present when carrying out the pinpoint tests, an
intermittent concern may be the cause. Always check for loose connections and corroded pins.
PINPOINT TEST A: THE MODULE DOES NOT RESPOND TO THE
DIAGNOSTIC TOOL — ANTI-LOCK BRAKE CONTROL MODULE tool —
instrument cluster zInstrument cluster. Test D .
z The module does not
respond to the diagnostic
tool — powertrain control
module (PCM) z
Wire or connection in SCP
communication network.
z PCM. z
GO to
Pinpoint Test E .
z No module/network
communication — ISO 9141
network z
Wire or connection in ISO
9141 communication
network.
z ISO 9141 networked
modules. z
GO to
Pinpoint Test F .
z No module/network
communication — SCP
network z
Wire or connection in SCP
communication network.
z SCP networked modules. z
GO to
Pinpoint Test G .
z No module/network
communication — no power
to the diagnostic tool z
CJB Fuse 31 (5A).
z DLC pins.
z Scan tool.
z Circuitry. z
GO to
Pinpoint Test H .
Test Step Result / Action to Take
A1 CHECK THE VEHICLE FOR TRACTION CONTROL
z
Check the vehicle for a traction control disable switch.
z Is a traction control disable switch present? Yes
GO to
A2 .
No
GO to A9 .
A2 CHECK ANTI-
LOCK BRAKE CONTROL MODULE C141
FOR DAMAGE z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Inspect the anti- lock brake control module C135 for
damage; repair as necessary.
z Connect: Anti- Lock Brake Control Module C135.
z Connect the diagnostic tool.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool: Diagnostic Data Link. Yes
GO to
A3 .
No
GO to A6 . Klj . 4 ba
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z
Was the result retrieved ABS: NO RESPONSE ON
CKT914 (BUS+)? A3 CHECK FOR OPEN BETWEEN DLC C251 AND ANTI-
LOCK BRAKE CONTROL MODULE C135 — CIRCUIT 914
(TN/OG) z
Key in OFF position.
z Disconnect the diagnostic tool.
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 Is the resistance less than 5 ohms? Yes
INSTALL a new anti-
lock brake
control module. REFER to
Section 206 - 09B . TEST the
system for normal operation.
No
GO to A4 .
A4 CHECK CIRCUIT 914 (TN/OG) BETWEEN DLC C251
AND IN- LINE C144 FOR OPEN z
Disconnect: In- Line C144.
z Check in-line C144 for damage; repair as necessary.
z Measure the resistance between in- line C144 Pin 6,
Circuit 914 (TN/OG), harness side and DLC C251 Pin 2,
Circuit 914 (TN/OG), harness side.
z Is the resistance less than 5 ohms? Yes
REPAIR Circuit 914 (TN/OG)
between anti-
lock brake control
module C135 and in- line C144.
For additional information,
REFER to Communication Circuit Wiring Repair . TEST the
system for normal operation.
No
GO to A5 .
A5 CHECK CIRCUIT 914 (TN/OG) BETWEEN DLC C251
AND IN- LINE C215 FOR OPEN z
Disconnect: In- Line C215.
z Check in-line C215 for damage; repair as necessary.
z Measure the resistance between in- line C215 Pin 10,
Circuit 914 (TN/OG), harness side and DLC C251 Pin 2,
Circuit 914 (TN/OG), harness side. Yes
REPAIR Circuit 914 (TN/OG)
between in-
line C144 and in- line
C215. For additional
information, REFER to
Communication Circuit Wiring Repair . TEST the system for
normal operation.
No
REPAIR Circuit 914 (TN/OG)
between DLC C251 and in- line
C215. For additional Klj . 5 ba
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z
Is the resistance less than 5 ohms? information, REFER to
Communication Circuit Wiring
Repair . TEST the system for
normal operation. A6 CHECK FOR OPEN BETWEEN DLC C251 AND ANTI-
LOCK BRAKE CONTROL MODULE C135 — CIRCUIT 915
(PK/LB) z
Key in OFF position.
z Disconnect the diagnostic tool.
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 Is the resistance less than 5 ohms? Yes
INSTALL a new anti-
lock brake
control module. REFER to
Section 206 - 09B . TEST the
system for normal operation.
No
GO to A7 .
A7 CHECK CIRCUIT 915 (PK/LB) BETWEEN DLC C251
AND IN- LINE C144 FOR OPEN z
Disconnect: In- Line C144.
z Check in-line C144 for damage; repair as necessary.
z Measure the resistance between in- line C144 Pin 13,
Circuit 915 (PK/LB), harness side and DLC C251 Pin
10, Circuit 915 (PK/LB), harness side.
z Is the resistance less than 5 ohms? Yes
REPAIR Circuit 915 (PK/LB)
between anti-
lock brake control
module C135 and in- line C144.
For additional information,
REFER to Communication Circuit Wiring Repair . TEST the
system for normal operation.
No
GO to A8 .
A8 CHECK CIRCUIT 915 (PK/LB) BETWEEN DLC C251
AND IN- LINE C215 FOR OPEN z
Disconnect: In- Line C215.
z Check in-line C215 for damage; repair as necessary.
z Measure the resistance between in- line C215 Pin 13,
Circuit 915 (PK/LB), harness side and DLC C251 Pin Yes
REPAIR Circuit 915 (PK/LB)
between in-
line C144 and in- line
C215. For additional Klj . 6 ba
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10, Circuit 915 (PK/LB), harness side.
z Is the resistance less than 5 ohms? information, REFER to
Communication Circuit Wiring
Repair . TEST the system for
normal operation.
No
REPAIR Circuit 915 (PK/LB)
between DLC C251 and in- line
C215. For additional
information, REFER to
Communication Circuit Wiring Repair . TEST the system for
normal operation. A9 CHECK FOR OPEN BETWEEN THE DLC C251 AND
ANTI- LOCK BRAKE CONTROL MODULE C135 — CIRCUIT
70 (LB/WH) z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Inspect anti- lock brake control module C135 for
damage, repair as necessary.
z Measure the resistance between anti- lock brake control
module C135 Pin 24, 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
INSTALL a new anti-
lock brake
control module. REFER to
Section 206 - 09A . TEST the
system for normal operation.
No
GO to A10 .
A10 CHECK FOR OPEN BETWEEN THE DLC C251 AND
IN- LINE C140 z
Disconnect: In- Line C140.
z Inspect in- line C140 for damage, repair as necessary.
z Measure the resistance between in- line C140 Pin 7,
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
REPAIR Circuit 70 (LB/WH)
between in-
line C140 and anti-
lock brake control module C135.
TEST the system for normal
operation.
No
GO to A11 .
A11 CHECK FOR OPEN BETWEEN THE DLC C251 AND
IN- LINE C314 z
Disconnect: In- Line C314.
z Inspect in- line C314 for damage, repair as necessary. Yes
REPAIR Circuit 70 (LB/WH) Klj . 7 ba
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