AC system FORD MUSTANG 2003 Workshop Manual

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 B: THE DAYTIME RUNNING LAMPS ARE ON WITH
THE PARKING BRAKE SET z
Is the voltage greater than 10 volts? A5 CHECK THE DRL MODULE GROUND —
CIRCUIT 1205
(BK) z
Measure the resistance between DRL module C1030 Pin
4, Circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
A6 .
No
REPAIR the circuit. TEST the
system for normal operation. A6 CHECK THE HIGH BEAM DISABLE INPUT CIRCUIT FOR
SHORT TO BATTERY — CIRCUIT 12 (LG/BK) z
Measure the voltage between DRL module C1030 Pin 5,
Circuit 12 (LG/BK), harness side and ground.
z Is voltage indicated? Yes
REPAIR the circuit. TEST the
system for normal operation.
No
INSTALL a new DRL module.
REFER to
Module — Daytime
Running Lamps (DRL) . TEST
the system for normal
operation. Test Step Result / Action to Take
B1 CHECK THE PARKING BRAKE SWITCH
z
Key in OFF position.
z Disconnect: Parking Brake Switch C306.
z Connect a 10A fused jumper wire between parking brake
switch C306, Circuit 22 (LB/BK), harness side and ground.
z Key in ON position. Yes
INSTALL a new parking
brake signal switch and
bracket. TEST the system
for normal operation.
No
GO to
B2 . Klj . 4 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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PINPOINT TEST D: THE LOW BEAM HEADLAMPS ARE ON AT FULL
INTENSITY IN DRL MODE
Test Step Result / Action to Take
D1 CHECK THE LOW BEAM
HEADLAMPS INPUT z
Disconnect: DRL Module
C1030.
z Are the low beam
headlamps still on at full
intensity? Yes
REFER to
Section 417 - 01 .
No
INSTALL a new DRL module. REFER to Module —
Daytime Running Lamps (DRL) . TEST the system for
normal operation. Klj . 6 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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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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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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