lock FORD MUSTANG 2003 Workshop Manual

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
22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

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
212003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...