FORD MUSTANG 2003 Workshop Manual

Short to Battery
B1434 Wiper HIGH and LOW Speed
Relay Coil Circuit Failure GEM GO to
Pinpoint Test B .
B1436 Wiper HIGH and LOW Speed
Relay Coil Circuit Short to Battery GEM GO to
Pinpoint Test B .
B1438 Wiper Mode Select Switch
Circuit Failure GEM GO to
Pinpoint Test B .
B1441 Wiper Mode Select Switch
Circuit Short to Ground GEM GO to
Pinpoint Test B .
B1446 Wiper Park Sense Circuit
Failure GEM GO to
Pinpoint Test B .
B1448 Wiper Park Sense Circuit Short
to Battery GEM GO to
Pinpoint Test B .
B1450 Wiper Wash/Delay Switch
Circuit Failure GEM GO to
Pinpoint Test C .
B1453 Wiper Wash/Delay Switch
Circuit Short to Ground GEM GO to
Pinpoint Test C .
B1458 Wiper Washer Pump Motor
Relay Circuit Failure GEM GO to
Pinpoint Test C .
B1460 Wiper Washer Pump Motor
Relay Coil Circuit Short to
Battery GEM GO to
Pinpoint Test C .
B1462 Safety Belt Switch Circuit
Failure GEM REFER to
Section 413 - 09 .
B1466 Wiper HIGH and LOW Speed
Not Switching GEM GO to
Pinpoint Test B .
B1473 Wiper Low Speed Circuit Motor
Failure GEM GO to
Pinpoint Test B .
B1476 Wiper High Speed Circuit Motor
Failure GEM GO to
Pinpoint Test B .
B1551 Decklid Release Circuit Failure GEM REFER to
Section 501 - 14B .
B1553 Decklid Release Circuit Short to
Battery GEM REFER to
Section 501 - 14B .
B1555 Ignition Run/Start Circuit Failure GEM REFER to
Section 211 - 05 .
B1687 Lamp Dome Input Circuit Short
to Battery GEM REFER to
Section 417 - 02 .
B2486 LF Side Repeater Lamp Output
Circuit Failure GEM REFER to
Section 417 - 01 .
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 . Klj . 4 ba
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Symptom Chart
Symptom Chart Condition
Possible Sources Action
z No communication with the
generic electronic module z
CJB Fuse 39 (5A).
z Circuitry.
z GEM. z
GO to
Pinpoint Test A .
z The wipers are inoperative zCJB Fuse 26 (30A).
z Ignition switch.
z Circuitry.
z GEM.
z Multifunction switch
(13K359).
z Wiper ON/OFF
relay.
z Wiper HIGH/LOW
relay.
z Wiper motor. z
GO to
Pinpoint Test B .
z The wipers stay on continuously zCircuitry.
z GEM.
z Multifunction
switch.
z Wiper ON/OFF
relay.
z Wiper HIGH/LOW
relay.
z Wiper motor. z
GO to
Pinpoint Test B .
z The HIGH and LOW wiper
speeds do not operate correctly z
Circuitry.
z GEM.
z Multifunction
switch.
z Wiper HIGH/LOW
relay.
z Wiper motor.
z DTC B1434. z
GO to
Pinpoint Test B .
z The intermittent wiper mode
does not operate correctly z
Circuitry.
z GEM.
z Multifunction
switch.
z Wiper motor. z
GO to
Pinpoint Test B .
z The washer pump is inoperative zCJB Fuse 26 (30A).
z Circuitry.
z GEM.
z Multifunction
switch.
z Washer pump
relay.
z Washer pump.
z Ignition switch. z
GO to
Pinpoint Test C .
z The low wiper speed does not
operate correctly z
Circuitry.
z Multifunction
switch.
z Wiper HIGH/LOW
relay.
z Wiper motor.
z GEM.
z DTC B1473.
z DTC B1434. z
GO to
Pinpoint Test B . Klj . 5 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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z
Is the voltage greater than 10 volts? B14 CHECK CIRCUIT 646 (YE/WH) FOR SHORT TO
GROUND BETWEEN GEM AND BJB z
Measure the resistance between GEM C201d Pin 12,
Circuit 646 (YE/WH), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
B15 .
No
REPAIR Circuit 646
(YE/WH). REPEAT the self-
test. CLEAR the DTCs. B15 CHECK CIRCUIT 646 (YE/WH) FOR OPEN BETWEEN
GEM AND BJB z
Measure the resistance between GEM C201d Pin 12,
Circuit 646 (YE/WH), harness side and BJB wiper ON/OFF
relay Pin 1, Circuit 646 (YE/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 Circuit 646
(YE/WH). REPEAT the self-
test. CLEAR the DTCs. B16 CHECK CIRCUITS 65 (DG) AND 61 (YE/RD) FOR OPEN
CONDITION BETWEEN BJB AND CJB z
Disconnect: Wiper HIGH/LOW Relay.
z Trigger the GEM active command WIPER RLY to ON.
z Measure the voltages between BJB wiper HIGH/LOW
relay Pin 86, Circuit 65 (DG), harness side and ground;
and between BJB wiper HIGH/LOW relay Pin 30, Circuit
61 (YE/RD), harness side and ground.
z Are the voltages greater than 10 volts? Yes
GO to
B17 .
No
REPAIR circuit in question.
REPEAT the self- test.
CLEAR the DTCs. B17 ISOLATE THE PROBLEM BETWEEN THE GEM AND
THE BJB z
Trigger the GEM active command WIPER RLY to ON. Yes Klj . 11 ba
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z
Connect a fused jumper wire (30A) between wiper
HIGH/LOW relay Pin 30, Circuit 61 (YE/RD), harness side
and Pin 87, Circuit 58 (WH), harness side.
z Did the wiper motor speed increase with the jumper
installed and slow down with the jumper removed? GO to
B18 .
No
GO to B26 .
B18 CARRY OUT COMPONENT TEST ON WIPER HIGH/LOW
RELAY z
Check the wiper HIGH/LOW relay; refer to Wiring
Diagrams, Cell 149, Component Testing.
z Is the wiper HIGH/LOW relay OK? Yes
GO to
B19 .
No
INSTALL a new wiper
HIGH/LOW relay. REPEAT
the self- test. CLEAR the
DTCs. B19 CHECK CIRCUIT 647 (GY/LB) FOR SHORT TO
BATTERY BETWEEN GEM AND BJB z
Disconnect: GEM C201d.
z Measure voltage between GEM C201d Pin 5, Circuit 647
(GY/LB), harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR Circuit 647 (GY/LB).
REPEAT the self-
test.
CLEAR the DTCs.
No
GO to B20 .
B20 CHECK CIRCUIT 647 (GY/LB) FOR SHORT TO GROUND
BETWEEN GEM AND BJB z
Measure the resistance between GEM C201d Pin 5,
Circuit 647 (GY/LB), harness side and ground. Yes
GO to
B21 .
No
REPAIR Circuit 647 (GY/LB).
REPEAT the self- test.
CLEAR the DTCs. Klj . 12 ba
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z
Is the resistance greater than 10,000 ohms? B21 CHECK CIRCUIT 647 (GY/LB) FOR OPEN CONDITION
BETWEEN GEM AND BJB z
Measure the resistance between GEM C201d Pin 5,
Circuit 647 (GY/LB), harness side and wiper HIGH/LOW
relay Pin 85, Circuit 647 (GY/LB), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new GEM.
REFER to
Section 419 - 10 .
REPEAT the self- test.
CLEAR the DTCs.
No
REPAIR Circuit 647 (GY/LB).
REPEAT the self- test.
CLEAR the DTCs. B22 CHECK CIRCUIT 61 (YE/RD) FOR OPEN CIRCUIT
CONDITION BETWEEN WIPER ON/OFF AND HIGH/LOW
RELAYS z
Disconnect: Wiper HIGH/LOW Relay.
z Disconnect: Wiper ON/OFF Relay.
z Measure the resistance between wiper ON/OFF relay Pin
3, Circuit 61 (YE/RD), harness side and wiper HIGH/LOW
relay Pin 30, Circuit 61 (YE/RD), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
B23 .
No
REPAIR Circuit 61 (YE/RD).
REPEAT the self- test.
CLEAR the DTCs. B23 CARRY OUT THE WIPER HIGH/LOW RELAY
COMPONENT TEST z
Check the wiper HIGH/LOW relay; refer to Wiring
Diagrams, Cell 149, Component Testing.
z Is the wiper HIGH/LOW relay OK? Yes
GO to
B24 .
No
INSTALL a new wiper
HIGH/LOW relay. REPEAT
the self- test. CLEAR the Klj . 13 ba
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