pinpoint FORD MUSTANG 2003 Workshop Manual

Pinpoint Tests
CAUTION: Before removing and installing the GEM or its connectors, disconnect the
battery. Failure to follow this caution will result in the GEM storing many erroneous DTCs and it
may exhibit erratic operation after installation.
CAUTION: Be careful when probing the central junction box (CJB), battery junction box
(BJB) or any connectors. Damage will result to the connector receptacle if the probe being
used is too large.
CAUTION: Electronic modules are sensitive to static electrical charges. If exposed to
these charges, damage may result.
NOTE: If continuous 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 terminals.
NOTE: Complete the entire pinpoint test related to the symptom before installing a new GEM.
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE (GEM) Test Step Result / Action to Take
CAUTION: Use the correct probe adapter(s) when making measurements. Failure to
use the correct probe adapter(s) may damage the connector. A1 CHECK THE GENERIC ELECTRONIC MODULE (GEM)
POWER SUPPLY z
Key in OFF position.
z Disconnect: Generic Electronic Module (GEM) C201a.
z Disconnect: GEM C201b.
z Key in ON position.
z Using the following table. measure the voltage between the
GEM, harness side and ground.
z Are the voltages greater than 10 volts? Connector Pin Circuit
C201a 4 400 (LB/BK)
C201a 1 1006 (DG/WH)
C201b 2 1001 (WH/YE)
C201b 3 193 (YE/LG) Yes
GO to
A2 .
No
REPAIR the circuit(s) in
question. TEST the system
for normal operation. A2 CHECK THE GEM GROUND CIRCUIT 397 (BK/WH) FOR
OPEN z
Key in OFF position.
z Measure the resistance between the GEM C201b pin 4,
circuit 397 (BK/WH), harness side and ground. Yes
GO to
A3 .
No
REPAIR the cirucit(s) in
question. TEST the system Klj . 6 ba
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PINPOINT TEST B: WINDSHIELD WIPERS DO NOT OPERATE /
OPERATE CORRECTLY z
Is the resistance less than 5 ohms? for normal operation.
A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
z
Measure the voltage between the GEM C201b pin 4, circuit
397 (BK/WH), harness side and ground.
z Is any voltage present? Yes
REPAIR the circuit. TEST
the system for normal
operation.
No
REFER to
Section 418 - 00 .
Test Step Result / Action to Take
B1 DETERMINE IF GEM IS RECEIVING CORRECT IGNITION
SWITCH STATUS z
Key in OFF position.
z Connect the diagnostic tool.
z NOTE: If the vehicle is equipped with a manual
transmission, depress the clutch while turning the ignition
switch to START.
z Monitor the GEM PIDs IGN_S, IGN_R IGN_A, and
IGN_KEY while turning the ignition switch through the
START, RUN, OFF and ACC positions.
z Do the GEM PID values agree with the ignition switch
positions? Yes
GO to
B2 .
No
REFER to Section 413 - 09 .
B2 DETERMINE IF GEM IS RECEIVING CORRECT WIPER
SWITCH STATUS FROM MULTIFUNCTION SWITCH z
Key in ON position.
z Monitor PID WPMODE, while moving through all wiper
control positions on the multifunction switch.
z Do the GEM PID values agree with switch positions? Yes
GO to
B3 .
No
GO to B6 .
B3 TEST GEM CONTROL OF WIPER ON/OFF RELAY
z
Trigger the GEM active command WIPER RLY ON and
OFF.
z Do the wipers turn ON and OFF? Yes
GO to
B4 . Klj . 7 ba
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PINPOINT TEST C: WINDSHIELD WASHERS DO NOT OPERATE /
OPERATE CORRECTLY z
Disconnect: Wiper Motor C125.
z Disconnect: GEM C201d.
z Measure the resistance between wiper motor C125 Pin 1,
Circuit 28 (BK/PK), harness side and GEM C201d Pin 1,
Circuit 58 (WH), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new wiper motor;
REFER to
Motor — Windshield
Wiper . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR Circuit 28 (BK/PK).
REPEAT the self- test.
CLEAR the DTCs. Test Step Result / Action to
Take C1 DETERMINE IF GEM IS RECEIVING CORRECT IGNITION
SWITCH STATUS z
Key in OFF position.
z Connect the diagnostic tool.
z NOTE: If the vehicle is equipped with a manual transmission,
depress the clutch while turning the ignition switch to START.
z Monitor the GEM PIDs IGN_S, IGN_R IGN_A, and IGN_KEY
while turning the ignition switch through the START, RUN, OFF
and ACC positions.
z Do the GEM PID values agree with the ignition switch
positions? Yes
GO to
C2 .
No
REFER to Section 413 - 09 .
C2 DETERMINE IF GEM IS RECEIVING CORRECT WIPER SWITCH
STATUS FROM MULTIFUNCTION SWITCH z
Key in ON position.
z Monitor GEM PID WPMODE while activating all wiper control
positions on the multifunction switch.
z Does the GEM PID values agree with switch positions? Yes
GO to
C3 .
No
GO to Pinpoint Test B .
C3 CHECK GEM CONTROL OF THE WASHER ON/OFF RELAY
z
Trigger GEM active command WASH RLY ON and OFF.
z Do washers turn ON and OFF? Yes
INSTALL a new GEM;
REFER to
Section 419 - 10 . REPEAT the
self- test. CLEAR the
DTCs.
No
GO to C4 .
C4 CHECK CIRCUIT 65 (DG) FOR OPEN CIRCUIT BETWEEN CJB
AND WASHER ON/OFF RELAY NOTE:
Verify voltage at CJB F26 (30A) before carrying out this Yes Klj . 15 ba
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Symptom Chart
PINPOINT TEST A: THE CONVERTIBLE TOP DOES NOT
RAISE/LOWER
SYMPTOM CHART Condition
Possible Sources Action
z The convertible top does not
raise/lower z
Convertible top
switch.
z Central junction box
(CJB) Fuse 20 (15A).
z Parking brake switch.
z Lower relay.
z Raise relay.
z Circuitry. z
Go To Pinpoint Test
A .
z The convertible top
hesitates/comes up uneven z
Convertible top
adjustment.
z Hydraulic lift
cylinders.
z Hydraulic system. z
Go To Pinpoint Test
B .
z The convertible top does not
raise or does not go up all the
way z
Convertible top
adjustment.
z Hydraulic lift
cylinders.
z Hydraulic system. z
Go To Pinpoint Test
C .
z The convertible top hydraulic
system z
Convertible top
adjustment.
z Hydraulic lift
cylinders.
z Hydraulic motor/pump
assembly.
z Hydraulic system. z
Go To Pinpoint Test
D .
Test Step Result / Action to
Take A1 CHECK THE CONVERTIBLE TOP OPERATION
NOTE:
The parking brake must be applied for the convertible top
system to operate.
z Key in ON position.
z Depress the convertible top switch in RAISE and LOWER
positions while listening for motor operation.
z Does the convertible top motor assembly operate in both
directions? Yes
Go To Pinpoint Test
C .
No
GO to A2 .
A2 CHECK THE POWER SUPPLY TO THE CONVERTIBLE TOP
SWITCH z
Key in OFF position.
z Disconnect: Convertible Top Switch C3115.
z Key in ON position.
z Measure the voltage between convertible top switch C3115 pin 4,
circuit 296 (WH/PK), harness side and ground. Yes
GO to
A3 .
No
REPAIR circuit 296
(WH/PK). TEST the
system for normal
operation. Klj . 2 ba
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PINPOINT TEST B: THE CONVERTIBLE TOP HESITATES/COMES UP
UNEVEN z
Is the resistance less than 5 ohms? A15 CHECK CIRCUIT 903 (RD) FOR AN OPEN
z
Disconnect: Raise Relay C4063.
z Measure the resistance between raise relay C4063 pin 30, circuit
903 (RD), harness side and convertible top motor C4062, circuit
903 (RD), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new raise
relay. TEST the
system for normal
operation.
No
REPAIR the circuit.
TEST the system for
normal operation.
A16 CHECK THE RAISE INPUT TO THE MOTOR
z
Key in ON position.
z Depress and hold the convertible top switch in the RAISE position.
z Measure the voltage between convertible top motor C4062, circuit
903 (RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new
convertible top motor;
REFER to
Hydraulic System, Lift Cylinder
and Motor in this
section. TEST the
system for normal
operation.
No
INSTALL a new raise
relay. TEST the
system for normal
operation. Test Step Result / Action to Take
B1 CHECK THE CONVERTIBLE TOP UP/DOWN
OPERATION NOTE:
The parking brake must be applied for the Yes Klj . 7 ba
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PINPOINT TEST C: THE CONVERTIBLE TOP DOES NOT RAISE OR
DOES NOT GO UP ALL THE WAY
PINPOINT TEST D: THE CONVERTIBLE TOP HYDRAULIC SYSTEM convertible top system to operate.
z Key in ON position.
z Actuate the convertible top switch to the LOWER
and RAISE positions.
z Did the convertible top operate to the full down
and full up position without hesitating? ADJUST the convertible top linkage.
TEST the system for normal
operation.
No
GO to
B2 .
B2 CHECK THE MOTOR OPERATION
z
Gain access to the convertible top motor/pump
assembly.
z Operate the convertible top to the LOWER and
RAISE positions while listening to the motor.
z Did the motor stop and then continue at any
time? Yes
Go To Pinpoint Test A
.
No
GO to B3 .
B3 CHECK THE CONVERTIBLE TOP LINKAGE
z
Operate the convertible top to the LOWER and
RAISE positions while observing the convertible
top linkage.
z Did the linkage operate smoothly without
binding? Yes
Go To Pinpoint Test D
.
No
ADJUST the convertible top linkage.
TEST the system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE CONVERTIBLE TOP OPERATION
NOTE:
The parking brake must be applied for the
convertible top system to operate.
z Key in ON position.
z Actuate the convertible top switch to the RAISE
position.
z Did the motor operate? Yes
GO to
C2 .
No
Go To Pinpoint Test A .
C2 CHECK THE CONVERTIBLE TOP LINKAGE
z
Operate the convertible top to the LOWER and
RAISE positions while observing the convertible
top linkage.
z Did the linkage bind and prevent the
convertible top from raising? Yes
ADJUST the convertible top linkage.
TEST the system for normal
operation.
No
Go To Pinpoint Test D
.
Test Step Result / Action to Take
D1 CHECK THE FLUID LEVEL
NOTE:
The fluid level should be even
with the bottom of the filler plug hole.
NOTE: Place an absorbent cloth
below the filler plug when checking
the fluid level.
z Remove the filler plug and check the Yes
GO to
D3 .
No
GO to D2 . Klj . 8 ba
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DIAGNOSIS AND TESTING
Air Bag Supplemental Restraint System (SRS)
Refer to Wiring Diagrams Cell
46 , Air Bag for schematic and connector information.
Restraint System Diagnostic Tool Warning WARNING: This tool is for restraint system service only. Remove from vehicle prior to
road use. Failure to remove could result in injury and possible violation of vehicle safety
standards.
Diagnosing Customer Concerns Without Hard DTCs
If a lamp fault code (LFC) is reported by the customer but is not present when the vehicle comes in for
service, follow the Diagnostic Instructions procedure in this section to identify the intermittent DTC.
Once the DTC is known, read the Normal Operation section of the pinpoint test for the DTC involved.
zFollow the deactivation procedure in this section.
z Determine the location of components involved in creating that code.
z Perform a thorough visual inspection of:
„components.
„ connectors.
„ splices and wiring harnesses.
„ pinched wires.
„ worn insulation on conductors.
Refer to the Possible Causes section of the pinpoint test for the DTC involved, which lists the common
concerns that relate to the DTC. Concerns are listed according to priority.
Diagnosing Customer Concerns with Hard DTCs
WARNING: The restraint system diagnostic tool is for restraint system service only.
Remove from vehicle prior to road use. Failure to remove could result in injury and possible
violation of vehicle safety standards. SECTION 501-
20B: Supplemental Restraint System 2003 Mustang Workshop Manual Special Tool(s)
Diagnostic Tool, Restraint
System
418-
F088 (105- R0012) Klj . 1 ba
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DIAGNOSIS AND TESTING
Diagnostic Instructions —
Air Bag Supplemental Restraint
System (SRS)
The symptom chart can be used to help locate the air bag supplemental restraint system (SRS)
concerns if no diagnostic trouble codes (DTCs) are retrieved and the listed symptoms are observed.
Whether or not the listed symptoms are observed, always perform the following.
1. Retrieve all DTCs stored in the restraints control module (RCM) memory. Refer to Retrieve/Clear Continuous DTCs in this section.
2. Run the On- Demand Self Test to determine what DTCs are currently being sensed by the
restraints control module (RCM) (14B321). Refer to On- Demand Self Test in this section.
3. If the stored DTCs are different than the current DTCs, always repair the current DTCs first.
4. If memory displays different continuous DTCs than the On- Demand Self-Test, perform in the
following order:
z On- Demand Self- Test.
z Memory (Retrieve/Clear Continuous DTCs).
A DTC can indicate several concerns. The DTCs are to assist in system diagnosis and are not to be
considered definitive. Always refer to the pinpoint test corresponding to the DTC to determine where
the concern lies and to repair the concern correctly.
The SRS diagnostics can be divided into three sections.
zDiagnostic test modes
z PID/data monitor and record
z Active command modes
Diagnostic Test Modes
Two menu options are available under the diagnostic test modes.
zRetrieve/Clear Continuous DTCs.
z On- Demand Self Test.
SECTION 501-
20B: Supplemental Restraint System 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool Klj . 1 ba
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2. Turn the ignition switch to the RUN position.
3. Follow manufacturer's instructions for the scan tool being used.
4. PIDs are continuously updated on the display.
Active Commands
This command allows the technician to verify operation of the air bag indicator and chime. When the
air bag output command is executed, the indicator and the chime are activated simultaneously for
approximately four seconds. Both devices are deactivated automatically.
Restraints Control Module (RCM) Diagnostic Trouble Code (DTC) Priority Table DTC
a LFC
b LFC
Priority Description Action To
Take — — 1 The Air Bag Indicator is Illuminated Continuously —
RCM
Disconnected, Inoperative, or Lost/Low Ignition Feed Go To Pinpoint
Test A .
B1342 24 2 RCM Is Faulted INSTALL a
new RCM.
B1231 19 3 RCM Crash Data Memory Full INSTALL a
new RCM.
B1921 21 4 RCM Bracket Ground Resistance High Go To Pinpoint
Test B .
C1414 29 5 Incorrect Vehicle Identification Code Go To Pinpoint
Test C .
B1887 15 6 Driver Air Bag Circuit Shorted to Ground Go To Pinpoint
Test D .
B1916 15 7 Driver Air Bag Circuit Shorted to Battery or Ignition Go To Pinpoint
Test E .
B1888 16 8 Passenger Air Bag Circuit Shorted to Ground Go To Pinpoint
Test F .
B1925 16 9 Passenger Air Bag Circuit Shorted to Battery or Ignition Go To Pinpoint
Test G .
B1932 32 10 Driver Air Bag Circuit Resistance High Go To Pinpoint
Test H .
B1933 33 11 Passenger Air Bag Circuit Resistance High Go To Pinpoint
Test I .
B1934 34 12 Driver Air Bag Circuit Resistance Low Go To Pinpoint
Test J .
B1935 35 13 Passenger Air Bag Circuit Resistance Low Go To Pinpoint
Test K .
B1892 — 17 Air Bag Tone Warning Indicator Circuit Shorted to
Ground or Open Go To Pinpoint
Test L .
B1891 — 18 Air Bag Tone Warning Indicator Circuit Shorted to Battery
or Ignition Go To Pinpoint
Test M .
B1869 Tone
c 19 Air Bag Indicator Inoperative Go To Pinpoint
Test N .
B1870 Tone
c 20 Air Bag Indicator Shorted to Battery Go To Pinpoint
Test O . Klj . 3 ba
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a
DTC: Diagnostic Trouble Code, retrieved using a scan tool.
b LFC: Lamp fault code, flashed on air bag indicator.
c Tone will sound only if additional DTCs are present.
Inspection and Verification 1. Verify the customer concern by checking the air bag indicator in the instrument cluster. Refer to Prove Out the System in this section.
2. Visually inspect for obvious signs of mechanical and electrical damage using the following chart:
3. If the concern is not visually evident, use the scan tool to retrieve diagnostic trouble codes (DTCs) and perform the on- demand self test.
4. WARNING: The restraint system diagnostic tool is for restraint system service only.
Remove from vehicle prior to road use. Failure to remove could result in injury and
possible violation of vehicle safety standards.
If the on- demand self test is passed and no DTCs are retrieved, GO to Symptom Chart .
5. If DTCs are retrieved, proceed to the Restraints Control Module (RCM) Diagnostic Trouble Code (DTC) Priority Table.
Symptom Chart — — — No Communication with the Restraints Control Module Go To Pinpoint
Test P .
Visual Inspection Chart Mechanical Electrical
z
Damaged restraints control module (RCM) bracket z
Open fuse(s)
z Damaged wiring harness
z Loose or corroded connectors
z Circuitry open/shorted Symptom Chart
Condition
Possible Sources Action
z Air bag warning indicator is
illuminated continuously z
Circuitry.
z Worn or damaged
connector component.
z RCM.
z Instrument cluster. z
Go To Pinpoint Test A .
z Air bag indicator flashing zAir bag SRS system
fault. z
REFER to DTC
Priority Table.
z Audible tone — DTCs
retrieved z
Air bag SRS system
fault. z
Go To Pinpoint Test N .
z Go To Pinpoint Test O .
z No communication with the zScan Tool. zGo To Pinpoint Klj . 4 ba
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