2003 FORD MUSTANG test G

z
Is the resistance greater than 10,000 ohms? F8 ISOLATE OPEN ON CIRCUIT 85 (BN/LB)
z
Disconnect: Safety Belt Switch C323.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Connect a 10A fused jumper wire between safety belt
switch C323 pin 2, circuit 85 (BN/LB), harness side and
ground while monitoring GEM PID D_SBELT.
z Does GEM PID GEM PID D_SBELT read OUT with
jumper wire installed? Yes
GO to
F10 .
No
GO to F9 .
F9 CHECK CIRCUIT 85 (BN/LB) FOR OPEN BETWEEN GEM
AND SEATBELT SWITCH z
Disconnect: Safety Belt Switch C323.
z Disconnect: GEM C201b.
z Measure the resistance between GEM C201b pin 8, circuit
85 (BN/LB), harness side and safety belt switch C323 pin 2,
circuit 85 (BN/LB), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
F11 .
No
REPAIR the circuit. CLEAR
the DTCs. TEST the system
for normal operation. F10 CHECK CIRCUIT 1205 (BK) FOR AN OPEN CIRCUIT
BETWEEN SAFETY BELT SWITCH AND GROUND z
Disconnect: Safety Belt Switch C323.
z Measure the resistance between the safety belt switch
C323 pin 1, circuit 1205 (BK), harness side and ground. Yes
INSTALL a new safety belt
switch. REPEAT the self-
test. CLEAR the DTCs. Klj . 19 ba
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z
Is the resistance less than 5 ohms? No
REPAIR the circuit. REPEAT
the self-
test. CLEAR the
DTCs. F11 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. Klj . 20 ba
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DIAGNOSIS AND TESTING
Charging System
Refer to Wiring Diagrams Cell
12 , Charging System for schematic and connector information.
Principles of Operation SECTION 414-
00: Charging System — General Information 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent SABRE Premium Battery and
Electrical System Tester
010-
00736 or equivalent Connector C102c End View
A Circuit 36 (YE/WH)
I Circuit 904 (LG/RD) Klj . 1 ba
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provide ventilation.
WARNING: When lifting a plastic- cased battery, excessive pressure on the end walls
could cause acid to spew through the vent caps resulting in personal injury, damage to the
vehicle or to the battery. Lift with a battery carrier or with your hands on opposite corners.
1. Verify the customer concern by operating the engine to duplicate the concern.
2. Inspect the charging system (battery, generator cable, harness connectors, connections) to determine if any obvious mechanical or electrical concerns exist. If found, repair as necessary
and test the system for normal operation. Refer to the following tables:
3. Check the operation of the charging system warning indicator lamp (instrument cluster). Normal operation is as follows:
zWith the ignition switch OFF, the charging system warning indicator should be OFF.
z With the ignition switch in RUN and the engine off, the charging system warning indicator
light should be on.
z With the engine running, the charging system warning indicator light should be off.
4. Verify the battery is being charged. Carry out the Battery— Load Test. Refer to Component
Tests in this section.
5. If the customer concern is verified after the initial inspection, refer to the Symptom Chart to determine which tests to carry out.
Symptom Chart Visual Inspection Chart
Mechanical Electrical
z
Battery case, posts, hold- down clamp, cables and
connections
z Generator drive (serpentine) belt for condition and
tension. Refer to Section 303 - 05 .
z Generator pulley z
Battery junction box (BJB)
fuse 20 (20A)
z Fuse links
z Circuitry
z Battery charge warning
indicator
z Cables
Normal Charging System Voltages Ignition
Switch
Position A Circuit
36
(YE/WH) I Circuit
904
(LG/RD) Generator B+
Circuit 38 (BK/OG) Battery Engine to
battery
ground Charging
System Warning Indicator
Operation OFF 12V 0V 12V 12V 0V Off
RUN-
engine off 12V 1-
3V 12V 12V 0V Illuminated
RUN-
engine
running 13-
15V 13-
15V 13-
15V 13-15V 0V Off Klj . 3 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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z
Is the voltage equal to battery positive voltage (B+)? B2 CHECK GENERATOR A CIRCUIT 36 (YE/WH)
z
Disconnect: Generator C102c (4.6L 4V) or C102a (3.8L or 4.6L
2V).
z Measure the voltage between the generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V) pin 3, circuit 36 (YE/WH), harness side
and ground.
z Is the voltage equal to battery positive voltage (B+)? Yes
GO to
B3 .
No
REPAIR the circuit.
TEST the system for
normal operation. B3 CHECK I CIRCUIT 904 (LG/RD) FOR AN OPEN
z
Key in ON position.
z With the ignition switch in the RUN position and the engine off,
measure the voltage between the generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V) pin 1, circuit 904 (LG/RD), harness side
and ground.
z Is the voltage equal to battery positive voltage (B+)? Yes
GO to
B4 .
No
REPAIR the circuit.
TEST the system for
normal operation. B4 CHECK FOR VOLTAGE DROP IN B+ CIRCUIT 38 (YE/WH)
z
Key in START position.
z With the engine at 2,000 rpm, measure the voltage drop between
the generator C102b, circuit 38 (BK/OG), component side and
positive battery terminal. Yes
INSTALL a new
generator. REFER to
Section 414
- 02 .
TEST the system for
normal operation.
No Klj . 6 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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