test G FORD MUSTANG 2003 Workshop Manual

Symptom Chart
Pinpoint Tests
CAUTION: Before removing and installing the GEM or its connectors, disconnect the Output Circuit Failure
B2488 RF Side Repeater Lamp
Output Circuit Failure GEM REFER to
Section 417 - 01 .
C1189 Brake Fluid Level Sensor
Input Short Circuit to Ground GEM REFER to
Section 413 - 01 .
C1223 Lamp Brake Warning
Output Circuit Failure GEM REFER to
Section 413 - 01 .
C1225 Lamp Brake Warning
Output Circuit Short to
Battery GEM REFER to
Section 413 - 01 .
Symptom Chart Condition
Possible Sources Action
z No communication with the generic
electronic module z
CJB Fuse 39
(5A)
z GEM.
z Circuitry. z
GO to
Pinpoint Test A .
z The courtesy lamps are inoperative zCJB Fuse 7
(20A).
z Door ajar switch
(es).
z Courtesy lamp
assemblies.
z Circuitry.
z GEM.
z Ignition Switch.
z Headlamp
Switch. z
GO to
Pinpoint Test B .
z The demand lighting is inoperative zCJB Fuse 7
(20A).
z Circuitry.
z GEM.
z Door ajar switch
(es).
z Demand lamp
assemblies.
z Ignition Switch.
z Headlamp
Switch. z
GO to
Pinpoint Test C .
z The illuminated entry is inoperative
when using the remote transmitter z
Remote
transmitter.
z GEM. z
GO to
Pinpoint Test D .
z The battery saver does not
deactivate after timeout z
Circuitry.
z GEM. z
GO to
Pinpoint Test E . Klj . 5 ba
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battery. Failure to follow this caution will result in the GEM storing many erroneous DTCs and
may result in the GEM exhibiting 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 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 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 2 400 (LB/BK)
C201a 3 1006 (DG/WH)
C201b 1 1001 (WH/YE)
C201b 4 193 (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 reistance between the GEM C201b pin 2, 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 . 6 ba
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PINPOINT TEST B: THE COURTESY LAMPS ARE INOPERATIVE z
Is the resistance less than 5 ohms? A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
z
Measure the voltage between GEM C201b pin 2, 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
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
positions? Yes
GO to
B2 .
No
For key- in-ignition
concerns, REFER to
Section 413 - 09 .
B2 CHECK THE DOOR AJAR INPUT TO THE GEM
z
Monitor the GEM PID D_DOOR, and P_DOOR, while
opening and closing the driver and passenger doors.
z Do the GEM PIDS D_DOOR and P_DOOR agree with the
driver and passenger door positions? Yes
GO to
B3 .
No
REFER to Section 413 -
09 .
B3 CHECK THE DOME LAMP SWITCH STATUS INPUT TO THE
GEM — MONITOR THE GEM PID DOMESW z
Monitor the GEM PID DOMESW, while activating, and
deactivating the dome lamp switch.
z Does the GEM PID DOMESW agree with the dome lamp
switch position? Yes
GO to
B4 .
No
GO to B13 .
B4 CHECK THE LUGGAGE COMPARTMENT LID AJAR INPUT
TO THE GEM — MONITOR THE GEM PID DECKLID Klj . 7 ba
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z
Monitor the GEM PID DECKLID, while opening and closing
the luggage compartment lid.
z Does the GEM PID DECKLID agree with the dome switch
position? Yes
GO to
B5 .
No
GO to B16 .
B5 CHECK THE COURTESY LAMP CIRCUITS
z
Close the luggage compartment lid and all doors are closed.
z Turn the dome and map lamp switches to the off position.
z Are the courtesy lamps illuminated? Yes
GO to
B12 .
No
GO to B6 .
B6 CHECK THE GEM CONTROL OF THE COURTESY LAMPS
z
Trigger the GEM active command COURTESYL ON and then
OFF.
z Do the courtesy lamps illuminate when the GEM active
command COURTESYL ON is triggered, and go out when
the GEM active command COURTESYL OFF is triggered? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
GO to B7 .
B7 CHECK THE GEM FOR AN INTERNAL FAULT
z
Trigger the GEM active command COURTESYL ON, then
OFF.
z Can an audible click be heard coming from the GEM,
while triggering the active command COURTESYL ON? Yes
GO to
B8 .
No
INSTALL a new GEM. For
additional information,
REFER to Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs. B8 CHECK CIRCUIT 1034 (BK/WH) FOR VOLTAGE
z
Disconnect the dome lamp C929 (coupe) or map lamp C978
(convertible)
z Trigger the GEM active command COURTESYL ON.
z Measure the voltage between dome/map lamp C929 (coupe)
Pin 3 or map lamp C978 (convertible) Pin 4, Circuit 1034
(BK/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
B11 .
No
GO to B9 .
B9 CHECK CIRCUIT 1006 (DG/WH) FOR OPEN
NOTE:
Verify battery voltage at CJB Fuse 7 (20A) before
carrying out this test.
z Disconnect: GEM C201a.
z Measure the voltage between GEM C201a Pin 1, Circuit 1006
(DG/WH), harness side and ground. Yes
GO to
B10 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. Klj . 8 ba
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z
Is the voltage greater than 10 volts? B10 CHECK CIRCUIT 1034 (BK/WH) FOR OPEN
z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c Pin 3, Circuit
1034 (BK/WH), harness side and dome/map lamp C929
(coupe) Pin 3 or map lamp C978 (convertible) Pin 4, Circuit
1034 (BK/WH), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B11 CHECK CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between dome/map lamp C929
(coupe) Pin 2 or map lamp C978 (convertible) Pin 1, Circuit
1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new
dome/map lamp
assembly. For additional
information, REFER to
Lamp Assembly
—
Map/Dome .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B12 CHECK CIRCUIT 1034 (BK/WH) FOR SHORT TO BATTERY
z
Measure the voltage between GEM C201c Pin 3, Circuit 1034
(BK/WH), harness side and ground. Yes
REPAIR the circuit.
REPEAT the self-
test.
CLEAR the DTCs.
No
INSTALL a new GEM. For
additional information,
REFER to Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs. Klj . 9 ba
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z
Is the voltage greater than 10 volts? B13 CHECK THE COURTESY LAMP OPERATION —
MONITOR
THE GEM PID DOMESW z
Monitor the GEM PID DOMESW, while moving the interior
lamp switch from the OFF to the ON position.
z Does the GEM PID DOMESW value always indicate ON? Yes
GO to
B15 .
No
GO to B14 .
B14 CHECK CIRCUIT 706 (GY) FOR OPEN
z
Disconnect: GEM C201e.
z Measure the voltage between GEM C201e Pin 21, Circuit 706
(GY), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B15 CHECK CIRCUIT 706 (GY) FOR SHORT TO BATTERY
z
Measure the voltage between GEM C201e Pin 21, Circuit 706
(GY), harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR the circuit.
REPEAT the self-
test.
CLEAR the DTCs.
No
INSTALL a new GEM. For
additional information,
REFER to Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs. B16 CHECK CIRCUIT 486 (BN/WH) FOR OPEN OR SHORT TO
GROUND — MONITOR THE GEM PID DECKLID z
Monitor the GEM PID DECKLID, while opening and closing
the luggage compartment lid.
z Does the GEM PID DECKLID agree with the luggage
compartment lid position? Yes
GO to
B17 .
No
GO to B19 . Klj . 10 ba
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B17 CHECK LUGGAGE COMPARTMENT SOLENOID FOR
SHORT TO GROUND z
Key in OFF position.
z Disconnect: Luggage Compartment Solenoid C430.
z Monitor the GEM PID DECKLID.
z Does the GEM PID DECKLID indicate closed? Yes
INSTALL a new luggage
compartment solenoid.
For additional information,
REFER to
Section 501 -
14A . REPEAT the self-
test. CLEAR the DTC.
No
GO to B18 .
B18 CHECK CIRCUIT 486 (BN/WH) FOR SHORT TO GROUND
z
Disconnect: GEM C201d.
z Measure the resistance between GEM C201d Pin 3, Circuit
486 (BN/WH), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B19 CHECK CIRCUIT 486 (BN/WH) FOR AN OPEN —
MONITOR
GEM PID DECKLID z
Disconnect: Luggage Compartment Solenoid C430.
z Monitor the GEM PID DECKLID.
z Connect a 10A fused jumper between luggage compartment
solenoid C430 Pin 3, Circuit 486 (BN/WH), harness side and
ground.
z Does the GEM PID DECKLID indicate AJAR with the
jumper installed? Yes
GO to
B21 .
No
GO to B20 .
B20 CHECK CIRCUIT 486 (BN/WH) FOR OPEN
z
Disconnect: GEM C201d.
z Measure the resistance between GEM C201d Pin 3, Circuit
486 (BN/WH), harness side and luggage compartment
solenoid C430 Pin 3, Circuit 486 (BN/WH) harness side. Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test. Klj . 11 ba
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PINPOINT TEST C: THE DEMAND LIGHTING IS INOPERATIVE z
Is the resistance less than 5 ohms? CLEAR the DTCs.
B21 CHECK GROUND CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between luggage compartment lid
switch C430 Pin 1, Circuit 1205 (BK), harness side and
ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new luggage
compartment solenoid.
For additional information,
REFER to
Section 501 -
14A . REPEAT the self-
test. CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. Test Step Result / Action to Take
C1 CHECK GEM SUPPLIED POWER TO THE DEMAND LAMPS
z
Turn on both map lamps by depressing the map lamp
switches.
z Turn on both vanity mirror lamps.
z Open the luggage compartment lid.
z Do any of the lamps illuminate? Yes
GO to
C8 .
No
GO to C2 .
C2 CHECK IGNITION STATES
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
positions? Yes
GO to
C3 .
No
For key- in-ignition
concerns, REFER to
Section 413 - 09 .
C3 CHECK DRIVER AND PASSENGER DOOR AJAR INPUTS TO
THE GEM z
Monitor the GEM PIDs D_DOOR and P_DOOR, while
opening and closing the driver and passenger doors.
z Did the GEM PIDs D_DOOR and P_DOOR agree with the
driver and passenger door positions? Yes
GO to
C4 .
No
REFER to Section 413 -
09 . Klj . 12 ba
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C4 CHECK INTERIOR LAMP SWITCH INPUT TO THE GEM —
MONITOR GEM PID DOMESW z
Monitor the GEM PID DOMESW, while moving the interior
lamp switch from the OFF to the ON position.
z Does the GEM PID DOMESW values agree with the
interior lamp switch positions? Yes
GO to
C5 .
No
GO to Pinpoint Test B .
C5 CHECK THE LUGGAGE COMPARTMENT LID AJAR INPUT
TO THE GEM — MONITOR THE GEM PID DECKLID z
Monitor the GEM PID DECKLID, while opening, and closing,
the luggage compartment lid.
z Does the GEM PID DECKLID agree with the luggage
compartment lid position? Yes
GO to
C6 .
No
GO to Pinpoint Test B .
C6 CHECK CIRCUIT 705 (LG/OG) FOR OPEN
z
Turn on both map lamps using the switches in the rear view
mirror.
z Turn on both vanity mirror lamps.
z Open the luggage compartment lid.
z Disconnect: GEM C201c.
z Connect a fused jumper (20A) between GEM C201c Pin 4,
Circuit 705 (LG/OG), harness side and battery positive
terminal.
z Do the demand lamps illuminate? Yes
GO to
C7 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. C7 CHECK CIRCUIT 1006 (DG/WH) FOR OPEN
NOTE:
Verify battery voltage at CJB Fuse 7 (20A) before
carrying out this test.
z Disconnect: GEM C201a.
z Measure the voltage between GEM C201a Pin 1, Circuit 1006
(DG/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. C8 CHECK CIRCUIT 705 (LG/OG) FOR VOLTAGE AT
INOPERATIVE DEMAND LAMP z
Key in OFF position.
z Disconnect inoperative demand lamp, dome/map C929 Yes
GO to
C9 . Klj . 13 ba
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PINPOINT TEST D: THE ILLUMINATED ENTRY IS INOPERATIVE
WHEN USING THE REMOTE TRANSMITTER (coupe), map C907 (convertible), right hand vanity C906, left
hand vanity C978, or luggage compartment C4111.
z Measure the voltage between inoperative demand lamp,
Circuit 705 (LG/OG), harness side and ground.
z Is the voltage greater than 10 volts? No
REPAIR the circuit in
question. REPEAT the
self-
test. CLEAR the
DTCs. C9 CHECK CIRCUIT 1205 (BK) FOR OPEN AT INOPERATIVE
DEMAND LAMP z
Measure the resistance between inoperative demand lamp
Circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new demand
lamp assembly. REPEAT
the self-
test. CLEAR the
DTCs.
No
REPAIR the circuit in
question. REPEAT the
self- test. CLEAR the
DTCs. Test Step Result / Action to Take
D1 CHECK THE REMOTE TRANSMITTER
INPUT TO THE GEM z
Remove the ignition key from the ignition.
z Depress the lock and then the unlock
buttons on the remote transmitter.
z Do the doors lock when the lock button
is depressed and unlock when the
unlock button is depressed? Yes
GO to
D2 .
No
REFER to Section 501 - 14B .
D2 CHECK OPERATION OF ILLUMINATED
ENTRY WITHOUT REMOTE TRANSMITTER z
Open the driver door.
z Do the courtesy lamps illuminate? Yes
INSTALL a new GEM. For additional
information, REFER to
Section 419 - 10 .
REPEAT the self- test. CLEAR the DTCs.
No
GO to Pinpoint Test B . Klj . 14 ba
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