pinpoint FORD MUSTANG 2003 Workshop Manual

Pinpoint Tests
CAUTION: Before removing and installing the generic electronic module (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), or any connectors.
Damage will result to the connector receptacle if the probe or terminal used is too large.
CAUTION: Electronic modules are sensitive to static discharges. 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.
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
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 circuit(s) in
question. TEST the system
for normal operation. Klj . 5 ba
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PINPOINT TEST B: THE KEY-
IN-IGNITION CHIME DOES NOT
OPERATE CORRECTLY z
Is the resistance less than 5 ohms? 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 CHECK IGNITION STATES
z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and IGN_R
while cycling the ignition switch through the OFF, ACC, RUN,
START and key out positions.
z Do the PID values agree with the ignition switch states? Yes
GO to
B2 .
No
GO to B4 .
B2 CHECK GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM Active Command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
B3 .
No
GO to B11 .
B3 CHECK GEM INPUT FROM DOOR AJAR CIRCUIT
z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_DR_SW, while opening and closing
the driver door.
z Do the GEM PID D_DR_SW values indicate CLOSED and
AJAR correctly? Yes
GO to
B11 .
No
Go To Pinpoint Test D .
B4 CHECK GEM INPUT VOLTAGE FROM IGNITION SWITCH AT Klj . 6 ba
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PINPOINT TEST C: A CHIME DOES NOT OPERATE CORRECTLY—
AIR BAG ground.
z Is the resistance greater than 10,000 ohms? No
REPAIR the circuit.
REPEAT the self-
test.
CLEAR the DTCs. B11 CHECK FOR CORRECT MODULE OPERATION
z
Check:
zfor corrosion
z for pushed- out pins
z connector seated correctly
z Connect any disconnected connectors.
z Make sure all other system connectors are fully seated.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new GEM.
REFER to
Section 419 -
10 . CLEAR the DTCs.
REPEAT the GEM 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. Test Step Result / Action to Take
C1 CHECK CONTINUOUS DTCS AND RESTRAINT CONTROL
MODULE (RCM) z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
RCM On- Demand Self- Test.
z Carry out Continuous DTCs and On Demand RCM Self-
Tests.
z Are any RCM DTCs received? Yes
REFER to
Section 501 - 20B .
No
GO to C2 .
C2 CHECK IGNITION STATES
z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and
IGN_R while cycling the ignition switch through the OFF,
ACC, RUN, START and key out positions.
z Do the PID values agree with the ignition switch
states? Yes
GO to
C3 .
No
Go To Pinpoint Test B .
C3 CHECK GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM active command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
C4 .
No Klj . 9 ba
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PINPOINT TEST D: THE DOOR AJAR CHIME DOES NOT OPERATE
CORRECTLY z
Is the resistance less than 5 ohms? C8 CHECK FOR CORRECT MODULE OPERATION
z
Check:
zfor corrosion
z for pushed- out pins
z connector seated correctly
z Connect any disconnected connectors.
z Make sure all other system connectors are fully seated.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new GEM.
REFER to
Section 419 - 10 .
CLEAR the DTCs. REPEAT
the GEM 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. Test Step Result / Action to Take
D1 CHECK IGNITION STATES
z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and
IGN_R while cycling the ignition switch through the OFF,
ACC, RUN, START and key out positions.
z Do the PID values agree with the ignition switch states? Yes
GO to
D2 .
No
GO to Pinpoint Test B .
D2 CHECK GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM active command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
D3 .
No
GO to D17 .
D3 CHECK GEM INPUT —
DRIVER DOOR AJAR CIRCUIT z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_DR_SW while opening and closing
the driver door.
z Do the GEM PID D_DR_SW values indicate CLOSED and
AJAR correctly? Yes
GO to
D4 .
No
GO to D5 .
D4 CHECK GEM INPUT —
PASSENGER DOOR AJAR CIRCUIT Klj . 11 ba
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PINPOINT TEST E: THE HEADLAMP ON REMINDER CHIME DOES
NOT OPERATE CORRECTLY z
Is the resistance less than 5 ohms? D16 CHECK CIRCUIT 1205 (BK) FOR OPEN BETWEEN
PASSENGER DOOR AJAR SWITCH AND GROUND z
Measure the resistance between passenger door ajar switch
C602 pin 1, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new passenger
door ajar switch. REFER to
Section 501
- 14A . REPEAT
the self- test. CLEAR the
DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. D17 CHECK FOR CORRECT MODULE OPERATION
z
Check:
zfor corrosion
z for pushed- out pins
z connector seated correctly
z Connect any disconnected connectors.
z Make sure all other system connectors are fully seated.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new GEM.
REFER to
Section 419 - 10 .
CLEAR the DTCs.
REPEAT the GEM 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. Test Step Result / Action to Take
E1 CHECK FOR CORRECT OPERATION OF THE HEADLAMP
SWITCH z
Cycle the headlamp switch through all positions to verify
correct operation of exterior lighting circuits.
z Do all exterior lamps operate correctly? Yes
GO to
E2 .
No
REFER to Section 417 - 01 . Klj . 15 ba
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E2 CHECK IGNITION STATES
z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and
IGN_R while cycling the ignition switch through the OFF,
ACC, RUN, START and key out positions.
z Do the PID values agree with the ignition switch
states? Yes
GO to
E3 .
No
Go To Pinpoint Test B .
E3 CHECK GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM active command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
E4 .
No
GO to E9 .
E4 CHECK GEM INPUT FROM DOOR AJAR CIRCUIT
z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_DR_SW while opening and closing
the driver door.
z Do the GEM PID D_DR_SW values indicate CLOSED
and AJAR correctly? Yes
GO to
E5 .
No
GO to Pinpoint Test D .
E5 MONITOR EXTERIOR LAMP INPUT FOR CORRECT
STATE z
Key in OFF position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID PARK_SW, while triggering the
headlamp switch ON and OFF.
z Do the GEM PID PARK_SW values indicate ON and
OFF correctly? Yes
GO to
E9 .
No
GO to E6 .
E6 CHECK EXTERIOR LAMP INPUT CIRCUIT FOR SHORT
TO POWER — GEM PID PARK_SW z
Key in OFF position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID PARK_SW, while opening and
closing the driver door.
z Does the GEM PID PARK_SW value always indicate
ON? Yes
GO to
E8 .
No
GO to E7 .
E7 CHECK CIRCUIT 14 (BN) FOR OPEN
z
Key in OFF position.
z Disconnect: GEM C201c.
z Disconnect: Headlamp Switch C205.
z Measure the resistance between GEM C201c pin 7, circuit
14 (BN), harness side and headlamp switch C205 pin R,
circuit 14 (BN), harness side. Yes
GO to
E9 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. Klj . 16 ba
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PINPOINT TEST F: THE SAFETY BELT WARNING CHIME DOES NOT
OPERATE CORRECTLY z
Is the resistance less than 5 ohms? E8 TEST CIRCUIT 14 (BN) FOR SHORT TO BATTERY
z
Key in OFF position.
z Disconnect: GEM C201c.
z Set the headlamp switch in the OFF position. Measure the
voltage between GEM C201c pin 7, circuit 14 (BN),
harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR the circuit. REPEAT
the self-
test. CLEAR the
DTCs.
No
GO to E9 .
E9 CHECK FOR CORRECT MODULE OPERATION
z
Check:
zfor corrosion
z for pushed- out pins
z connector seated correctly
z Connect any disconnected connectors.
z Make sure all other system connectors are fully seated.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new GEM.
REFER to
Section 419 - 10 .
CLEAR the DTCs. REPEAT
the GEM 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. Test Step Result / Action to Take
F1 CHECK IGNITION STATES
NOTE:
Verify the belt minder is activated before
diagnosing.
z Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID. Yes
GO to
F2 .
No
Go To Pinpoint Test B . Klj . 17 ba
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Pinpoint Tests
CAUTION: Do not make jumper connections except as directed. Incorrect connections
may damage the voltage regulator test terminals, fuses, or fuse links.
CAUTION: Do not allow any metal object to come in contact with the generator housing
and internal diode cooling fins.
NOTE: All voltage measurements are referenced to the negative (- ) battery post unless otherwise
specified. PINPOINT TEST A: BATTERY IS DISCHARGED OR VOLTAGE IS Symptom Chart
Condition
Possible Sources Action
z Battery is discharged or voltage is
low z
Circuitry.
z High key- off current
drain(s).
z Battery.
z Generator. z
Go To Pinpoint
Test A .
z The charging system warning
indicator is on with the engine
running (the system voltage does
not increase) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test B .
z The system overcharges (the
battery voltage is greater than 15.5
volts) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test C .
z The charging system warning
indicator is on with the engine
running and the battery increases
voltage z
Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test D .
z The charging system warning
indicator is off with the ignition
switch in the RUN position and the
engine off z
Bulb.
z Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test E .
z The charging system warning
indicator flickers or is intermittent z
Central junction box
(CJB) fuse 5 (15A).
z Generator
connector
unplugged (C102a).
z Circuitry.
z Generator. z
Go To Pinpoint
Test F .
z The generator is noisy zBolts or brackets.
z Drive belt.
z Generator or pulley. z
Go To Pinpoint
Test G .
z Radio interference zGenerator.
z Circuitry.
z In-vehicle
entertainment
system. z
Go To Pinpoint
Test F . Klj . 4 ba
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LOW
PINPOINT TEST B: THE CHARGING SYSTEM WARNING INDICATOR
IS ON WITH THE ENGINE RUNNING (THE BATTERY VOLTAGE
DOES NOT INCREASE)
Test Step Result / Action to Take
A1 CHECK BATTERY CONDITION
z
Carry out the Battery— Condition Test to determine if
the battery can hold a charge and is OK for use.
Refer to Section 414 - 01 .
z Is the battery OK? Yes
GO to
A2 .
No
INSTALL a new battery. REFER
to Section 414 - 01 . TEST the
system for normal operation. A2 CHECK THE GENERATOR OUTPUT
z
Carry out the On- Vehicle Generator Load/No Load
Test. Refer to Component Tests in this section.
z Is the generator OK? Yes
GO to
A3 .
No
GO to Pinpoint Test B .
A3 CHECK FOR CURRENT DRAINS
z
Carry out the Battery— Drain Test. Refer to
Component Tests in this section.
z Are there any excessive current drains? Yes
REPAIR as necessary. TEST the
system for normal operation.
No
GO to
A4 .
A4 CHECK FOR CURRENT DRAINS WHICH SHUT OFF
WHEN THE BATTERY IS DISCONNECTED z
Carry out the Battery— Electronic Drains Which Shut
Off When the Battery Cable is Disconnected Test.
Refer to Component Tests in this section.
z Are there any current drains which shut off when
the battery is disconnected? Yes
REPAIR as necessary. TEST the
system for normal operation.
No
GO to
Pinpoint Test B .
Test Step Result / Action to
Take B1 CHECK GENERATOR B+ CIRCUIT 38 (BK/OG)
z
Disconnect: Generator B+ C102b.
z Measure the voltage between the generator C102b, circuit 38
(BK/OG), component side and ground. Yes
GO to
B2 .
No
REPAIR the circuit.
TEST the system for
normal operation. Klj . 5 ba
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PINPOINT TEST C: THE SYSTEM OVERCHARGES (THE BATTERY
VOLTAGE IS GREATER THAN 15.5 VOLTS)
PINPOINT TEST D: THE CHARGING SYSTEM WARNING INDICATOR
IS ON WITH THE ENGINE RUNNING AND THE BATTERY z
Is the voltage drop less than 0.5 volt? REPAIR high
resistance in the B+
circuit 38 (BK/OG).
TEST the system for
normal operation.
Test Step Result / Action to Take
C1 CHECK FOR VOLTAGE DROP IN A CIRCUIT 36 (YE/WH)
z
Disconnect: Generator C102c (4.6L 4V) or C102a (3.8L or 4.6L
2V).
z Key in ON position.
z Measure the voltage drop between the generator C102c (4.6L
4V) or C102a (3.8L or 4.6L 2V) pin 3, circuit 36 (YE/WH),
harness side and positive battery terminal.
z Is the voltage drop less than 0.5 volt? Yes
GO to
C2 .
No
REPAIR the high
resistance in A circuit 36
(YE/WH). TEST the
system for normal
operation. C2 CHECK GENERATOR AND BATTERY GROUND
CONNECTIONS z
Key in OFF position.
z Check the ground connections between the voltage regulator
and the generator and the engine, and the battery and the
engine.
z Are all ground connections clean and tight? Yes
INSTALL a new
generator. REFER to
Section 414
- 02 . TEST
the system for normal
operation.
No
REPAIR ground
connections as
necessary. TEST the
system for normal
operation. Klj . 7 ba
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