key FORD MUSTANG 2003 Workshop Manual

6. If the DTCs retrieved are related to the concern, go to GEM Diagnostic Trouble Code (DTC)
Index to continue diagnostics.
7. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.
GEM Diagnostic Trouble Code (DTC) Index GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1217 Horn Relay Coil Circuit Failure GEM REFER to
Section 413 - 06 .
B1218 Horn Relay Coil Circuit Short to
Vbatt GEM REFER to
Section 413 - 06 .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 417 - 01 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
B1322 Driver Door Ajar Circuit Short to
Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1339 Chime Input Request Circuit
Short to Battery (FOJ) GEM REFER to
Section 413 - 09 .
B1340 Chime Input Request Circuit
Short to Ground GEM REFER to
Section 413 - 09 .
B1342 ECU Is Defective GEM CLEAR the DTCs. Retrieve the DTCs. If DTC
B1342 is retrieved, INSTALL a new GEM. REFER to Section 419 - 10 .
B1353 Ignition Key-
In Circuit Open GEM REFER to
Section 413 - 09 .
B1359 Ignition Run/Acc Circuit Failure GEM REFER to
Section 211 - 05 .
B1396 Power Door Lock Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
B1397 Power Door Unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1405 Driver Power Window Down
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1408 Driver Power Window Up Circuit
Short to Battery GEM REFER to
Section 501 - 11 .
B1410 Driver Power Window Motor
Circuit Failure GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit Short
to Battery GEM REFER to
Section 413 - 01 .
B1428 Lamp Safety Belt Circuit Failure GEM REFER to
Section 413 - 01 .
B1431 Wiper Brake/Run Relay Circuit
Failure GEM GO to
Pinpoint Test B .
B1432 Wiper Brake/Run Relay Circuit GEM GO to
Pinpoint Test B . Klj . 3 ba
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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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No
GO to
B10 .
B4 TEST THE GEM CONTROL OF WIPER HIGH/LOW RELAY
z
Trigger the GEM active command WIPER RLY to ON.
z Trigger the GEM active command SPEED RLY ON and
OFF.
z Does wiper speed change on activation and
deactivation of SPEED RLY command? Yes
GO to
B5 .
No
GO to B16 .
B5 DETERMINE IF GEM IS RECEIVING CORRECT WIPER
POSITION STATUS z
Monitor GEM PID WPPRKSW while turning the wipers ON
using the multifunction switch.
z Do the PID values agree with the wiper position? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 - 10 .
CLEAR the DTCs. REPEAT
the self- test.
No
GO to B27 .
B6 TEST THE MULTIFUNCTION SWITCH FOR NORMAL
OPERATION z
Disconnect: Multifunction Switch C202a.
z Check the multifunction switch. Refer to Wiring Diagrams,
Cell 149, Component Testing.
z Is the multifunction switch OK? Yes
GO to
B7 .
No
INSTALL a new multifunction
switch; REFER to Section 211 - 05 . REPEAT the self-
test. CLEAR the DTCs. B7 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680
(LB/OG) FOR SHORT TO BATTERY BETWEEN THE GEM
AND THE MULTIFUNCTION SWITCH z
Disconnect: GEM C201e.
z Key in ON position.
z Using the following table, measure the voltage between
the GEM C201e Pins, harness side and ground.
z Are the voltages greater than 10 volts? Pin Circuit
5 682 (DB)
18 684 (PK/YE)
19 680 (LB/OG) Yes
REPAIR the circuit(s) in
question. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B8 .
B8 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680 Klj . 8 ba
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(LB/OG) FOR SHORT TO GROUND BETWEEN THE GEM AND
THE MULTIFUNCTION SWITCH
z
Key in OFF position.
z Using the following table, measure the resistance between
the GEM C201e Pins, harness side and ground.
z Are the resistances greater than 10,000 ohms? Pin Circuit
5 682 (DB)
18 684 (PK/YE)
19 680 (LB/OG) Yes
REPAIR the circuit(s) in
question. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B9 .
B9 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680
(LB/OG) FOR AN OPEN CONDITION BETWEEN GEM AND
MULTIFUNCTION SWITCH z
Using the following table, measure the resistance between
the GEM C201e Pins, harness side and multifunction
switch C202a Pins, harness side.
z Are the resistances less than 5 ohms? GEM Multifunction Switch Circuit
C260 Pin 5 C202a Pin 685 682 (DB)
C260 Pin 18 C202a Pin 590 684 (PK/YE)
C260 Pin 19 C202a Pin 993 680 (LB/OG) Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 - 10 .
REPEAT the self- test.
CLEAR the DTCs.
No
REPAIR circuit(s) in question.
REPEAT the self- test.
CLEAR the DTCs. B10 CHECK CIRCUITS 65 (DG) FOR OPEN CIRCUIT
CONDITION BETWEEN BJB AND CJB NOTE:
Verify voltage at CJB F26 (30A) before carrying out
this test.
z Disconnect: Wiper On/Off Relay.
z Measure the voltage between BJB ON and OFF wiper Yes
GO to
B11 .
No Klj . 9 ba
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relay Pin 5, Circuit 65 (DG), harness side and ground; and
between BJB wiper ON/OFF relay Pin 2, Circuit 65 (DG),
harness side and ground.
z Are the voltages greater than 10 volts? REPAIR circuit(s) in question.
REPEAT the self-
test.
CLEAR the DTCs. B11 ISOLATE PROBLEM BETWEEN GEM AND BJB
z
Key in OFF position.
z Connect a fused jumper wire (30A) between wiper
ON/OFF relay Pin 3 and Pin 5, harness side.
z Key in ON position.
z Did the wiper motor activate? Yes
GO to
B12 .
No
GO to B22 .
B12 CARRY OUT THE WIPER ON/OFF RELAY COMPONENT
TEST z
Check the wiper ON and OFF relay; refer to Wiring
Diagrams, Cell 149, Component Testing.
z Is the ON/OFF wiper relay OK? Yes
GO to
B13 .
No
INSTALL a new wiper
ON/OFF relay. REPEAT the
self- test. CLEAR the DTCs. B13 CHECK CIRCUIT 646 (YE/WH) FOR SHORT TO
BATTERY BETWEEN GEM AND BJB z
Disconnect: Wiper On/Off Relay.
z Disconnect: GEM C201d.
z Measure the voltage between GEM C201d 3 Pin 12,
Circuit 646 (YE/WH), harness side and ground. Yes
REPAIR Circuit 646
(YE/WH). REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B14 . Klj . 10 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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z
Is the voltage greater than 10 volts? A3 CHECK CIRCUIT 588 (VT) FOR AN OPEN
z
Key in OFF position.
z Connect: Convertible Top Switch C3115.
z Disconnect: Raise Relay C4063.
z Key in ON position.
z Depress and hold the convertible top switch in the RAISE position.
z Measure the voltage between raise relay C4063 pin 85, circuit 588
(VT), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A4 .
No
GO to A5 .
A4 CHECK CIRCUIT 688 (GY/LB) FOR VOLTAGE
z
Key in OFF position.
z Disconnect: Lower Relay C4064.
z Key in ON position.
z Depress and hold the convertible top switch in the LOWER
position.
z Measure the voltage between lower relay C4064 pin 85, circuit
688 (GY/LB), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A9 .
No
GO to A8 .
A5 CHECK CIRCUIT 588 (VT) FOR OPEN
z
Key in OFF position.
z Disconnect: Convertible Top Switch C3115.
z Measure the resistance between convertible top switch C3115 pin
3, circuit 588 (VT), harness side and raise relay C4063 pin 85, Yes
INSTALL a new
convertible top switch.
REFER to
Convertible Klj . 3 ba
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circuit 588 (VT), harness side.
z Is the resistance less than 5 ohms? Top Switch in this
section. TEST the
system for normal
operation.
No
REPAIR Circuit 588
(VT). TEST the
system for normal
operation. A6 CHECK CIRCUIT 688 (GY/LB) FOR OPEN
z
Key in OFF position.
z Disconnect: Convertible Top Switch C3115.
z Measure the resistance between convertible top switch C3115 pin
5, circuit 688 (GY/LB), harness side and lower relay C4064 pin 85,
circuit 688 (GY/LB), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new
convertible top switch.
REFER to
Convertible Top Switch in this
section. TEST the
system for normal
operation.
No
REPAIR circuit 688
(GY/LB). TEST the
system for normal
operation. A7 CHECK THE BATTERY SUPPLY TO THE RELAYS
z
Measure the voltage between raise relay C4063 pin 87, circuit 170
(RD/LB), harness side and ground; and between lower relay
C4064 pin 87, circuit 170 (RD/LB), harness side and ground.
z Are the voltages greater than 10 volts? Yes
GO to
A8 .
No
REPAIR circuit 170
(RD/LB). TEST the
system for normal
operation. A8 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between raise relay C4063 pin 87A,
circuit 1205 (BK), harness side and ground; and between lower
relay C4064 pin 87A, circuit 1205 (BK), harness side and ground. Yes
GO to
A9 .
No
REPAIR the circuit.
TEST the system for
normal operation. Klj . 4 ba
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