AC system FORD MUSTANG 2003 Workshop Manual

Pinpoint Tests
PINPOINT TEST J: THE TURN SIGNAL LAMPS ARE NEVER ON z
Electronic flasher.
z The hazard
flasher lamps are
never on z
Central junction
box (CJB) fuse 13
(15A).
z Circuitry.
z Multifunction
switch.
z Electronic flasher. z
Go To Pinpoint Test K .
z One turn
signal/hazard
lamp is never on z
Turn
signal/hazard
flasher lamp.
z Circuitry. z
REPAIR inoperative turn
signal/hazard flasher lamp
circuit
„LF Circuit 3 (LG/WH).
„ RF Circuit 2 (WH/LB).
„ LR Circuit 9 (LG/OG).
„ RR Circuit 5 (OG/LB).
z The turn signal
lamps are always
on z
Multifunction
switch. z
INSTALL a new multifunction
switch; REFER to Section 211 -
05 . TEST the system for
normal operation.
z The hazard
flasher lamps are
always on z
Multifunction
switch. z
INSTALL a new multifunction
switch; REFER to Section 211 -
05 . TEST the system for
normal operation. Test Step Result / Action to
Take J1 CHECK THE VOLTAGE TO THE ELECTRONIC FLASHER
z
Disconnect: Electronic Flasher C2141.
z Key in ON position.
z Measure the voltage between the following electronic flasher
C2141 circuits, harness side and ground.
„Pin 2, Circuit 1039 (BK/YE).
„ Pin 3, Circuit 383 (RD/WH).
z Are the voltages greater than 10 volts? Yes
GO to
J2 .
No
REPAIR the circuit in
question. TEST the
system for normal
operation. J2 CHECK CIRCUIT 44 (LB)
z
Key in OFF position. Yes Klj . 2 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

PINPOINT TEST K: THE HAZARD FLASHER LAMPS ARE NEVER ON z
Disconnect: Multifunction Switch C202b.
z Measure the resistance between multifunction switch C202b Pin
44, Circuit 44 (LB), harness side and the electronic flasher C2141
Pin 1, Circuit 44 (LB), harness side; and between multifunction
switch C202b Pin 44, Circuit 44 (LB), harness side and ground.
z Is the resistance less than 5 ohms between the multifunction
switch and the electronic flasher, and greater than 10,000
ohms between the multifunction switch and ground? GO to
J3 .
No
REPAIR the circuit.
TEST the system for
normal operation. J3 CHECK THE CONTINUITY OF THE MULTIFUNCTION SWITCH
z
Carry out the multifunction switch component test.
Refer to Wiring Diagrams Cell 149 for schematic and connector
information.
z Is the switch OK? Yes
INSTALL a new
electronic flasher.
TEST the system for
normal operation.
No
INSTALL a new
multifunction switch.
REFER to
Section 211 - 05 . TEST the
system for normal
operation. Test Step Result / Action to
Take K1 CHECK THE VOLTAGE TO THE ELECTRONIC FLASHER
z
Disconnect: Electronic Flasher C2141.
z Measure the voltage between electronic flasher C2141 Pin 3,
Circuit 383 (RD/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
K2 .
No
REPAIR the circuit.
TEST the system for
normal operation. K2 CHECK CIRCUIT 385 (WH/RD)
z
Disconnect: Multifunction Switch C202b. Yes Klj . 3 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

z
Measure the resistance between multifunction switch C202b Pin
385, Circuit 385 (WH/RD), harness side and electronic flasher
C2141 Pin 4, Circuit 385 (WH/RD), harness side; and between
multifunction switch C202b Pin 385, Circuit 385 (WH/RD), harness
side and ground.
z Is the resistance less than 5 ohms between the multifunction
switch and the electronic flasher, and greater than 10,000
ohms between the multifunction switch and ground? GO to
K3 .
No
REPAIR the circuit.
TEST the system for
normal operation. K3 CHECK THE CONTINUITY OF THE MULTIFUNCTION SWITCH
z
Carry out the multifunction switch component test.
Refer to Wiring Diagrams Cell 149 for schematic and connector
information.
z Is the switch OK? Yes
INSTALL a new
electronic flasher.
TEST the system for
normal operation.
No
INSTALL a new
multifunction switch;
REFER to
Section 211 - 05 . TEST the
system for normal
operation. Klj . 4 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests
PINPOINT TEST L: THE PARKING, REAR OR LICENSE LAMPS ARE
INOPERATIVE
PINPOINT TEST M: ONE OR MORE PARKING, REAR OR LICENSE
LAMP(S) IS INOPERATIVE
Test Step Result / Action to Take
L1 CHECK THE VOLTAGE TO THE HEADLAMP SWITCH
z
Disconnect: Headlamp Switch C205.
z Measure the voltage between headlamp switch C205 Pin
B2, Circuit 195 (TN/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
L2 .
No
REPAIR the circuit. TEST the
system for normal operation. L2 CHECK CIRCUIT 14 (BN) FOR OPEN
z
Measure the resistance between headlamp switch C205
Pin R, Circuit 14 (BN), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new headlamp
switch; REFER to
Lamp Switch — Headlamp . TEST the
system for normal operation.
No
REPAIR the circuit. TEST the
system for normal operation. Test Step Result / Action to Take
M1 CHECK THE VOLTAGE TO THE INOPERATIVE
LAMP(S) z
Key in OFF position.
z Disconnect: Inoperative Lamp.
z Place the headlamp switch in the parking lamps
ON position.
z Measure the voltage between inoperative lamp
connector Circuit 14 (BN), harness side and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR Circuit 1205 (BK) for an open.
TEST the system for normal operation.
No
REPAIR the circuit. TEST the system
for normal operation. Klj . 2 ba
32003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

PINPOINT TEST N: THE PARKING, REAR OR LICENSE LAMPS ARE
ON CONTINUOUSLY
Test Step Result / Action to Take
N1 CHECK THE HEADLAMP
SWITCH z
Key in OFF position.
z Disconnect: Headlamp
Switch C205.
z Key in ON position.
z Are the parking, rear or
licences lamps on? Yes
REPAIR Circuit 14 (BN) for a short to battery. TEST the
system for normal operation.
No
INSTALL a new headlamp switch; REFER to
Lamp Switch — Headlamp . TEST the system for normal operation. Klj . 3 ba
32003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests
PINPOINT TEST O: THE FOG LAMPS ARE INOPERATIVE Condition
Possible Sources Action
z The fog lamps are
inoperative z
BJB Fuse 27 (20A).
z CJB Fuse 38 (20A).
z Circuitry.
z Fog lamp relay.
z Fog lamp interrupt
relay.
z Headlamp switch.
z Fog lamp switch.
z Multifunction switch. z
GO to Pinpoint Test O .
z The individual fog lamp is
inoperative z
Fog lamp bulb.
z Circuitry. z
GO to Pinpoint Test P .
z The fog lamps are on
continuously z
Fog lamp relay.
z Circuitry.
z Fog lamp switch. z
GO to Pinpoint Test Q .
Test Step Result / Action
to Take O1 CHECK THE PARK LAMPS
z
Place the headlamp switch in the PARK position.
z Place the multifunction switch in low beam position.
z Do the park lamps illuminate? Yes
Turn off the
headlamp switch.
GO to
O2 .
No
GO to Pinpoint Test L .
O2 CHECK THE FOG LAMP RELAYS
z
Disconnect: Fog Lamp Relay.
z Disconnect: Fog Lamp Interrupt Relay.
z Check the fog lamp relay and fog lamp interrupt relay; refer to Wiring
Diagrams Cell 149.
z Are the relays OK? Yes
GO to
O3 .
No
INSTALL new
relay(s). TEST
the system for
normal
operation. O3 CHECK THE CIRCUIT 12 (LG/BK)
z
Measure the voltage between fog lamp interrupt relay connector Pin 1,
Circuit 12 (LG/BK), harness side and ground. Yes
GO to
O4 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. Klj . 2 ba
62003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

z
Is the voltage greater than 0 volts? O4 CHECK CIRCUIT 275 (YE)
z
Measure the resistance between fog lamp interrupt relay connector Pin
4, Circuit 275 (YE), harness side and fog lamp relay connector Pin 85,
Circuit 275 (YE), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
O5 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. O5 CHECK CIRCUIT 477 (LB/BK) FOR OPEN
z
Measure the voltage between fog lamp relay connector Pin 30, Circuit
477 (LB/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
O6 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. O6 CHECK CIRCUIT 188 (WH/BK)
z
Disconnect: Fog Lamp Switch C240.
z Measure the resistance between fog lamp switch C240 Pin 1, Circuit
188 (WH/BK), harness side and fog lamp relay connector Pin 86,
Circuit 188 (WH/BK), harness side; and between fog lamp switch C240
Pin 1, Circuit 188 (WH/BK), harness side and ground. Yes
GO to
O7 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. Klj . 3 ba
62003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

PINPOINT TEST P: THE INDIVIDUAL FOG LAMP IS INOPERATIVE z
Is the resistance less than 5 ohms? O7 CHECK CIRCUIT 1205 (BK)
z
Measure the resistance between fog lamp interrupt relay connector Pin
2, Circuit 1205 (BK), and ground.
z Is the resistance less than 5 ohms? Yes
GO to
O8 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. O8 CHECK THE FOG LAMP SWITCH
z
Measure the resistance between fog lamp switch C240 Pin 1, Circuit
188 (WH/BK), connector side and fog lamp switch C240 Pin 2, Circuit
14 (BN), connector side with the fog lamp switch on.
z Is the resistance less then 5 ohms? Yes
REPAIR Circuit
478 (TN/OG).
TEST the system
for normal
operation.
No
INSTALL a new
fog lamp switch.
TEST the system
for normal
operation.
Test Step Result / Action to
Take P1 CHECK THE GROUND TO THE FOG LAMP
z
Key in OFF position.
z Disconnect: Inoperative Fog Lamp.
z Measure the resistance between inoperative fog lamp C162 Pin
1 (RH) or C152 Pin 1 (LH), Circuit 1205 (BK), harness side and
ground. Yes
REPAIR Circuit 478
(TN/OG) for open.
TEST the system for
normal operation. Klj . 4 ba
62003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

PINPOINT TEST Q: THE FOG LAMPS ARE ON CONTINUOUSLY z
Is the resistance less than 5 ohms? No
REPAIR Circuit 1205
(BK). TEST the system
for normal operation.
Test Step Result / Action to Take
Q1 CHECK THE FOG LAMP RELAY
z
Disconnect: Fog Lamp Relay.
z Are the fog lamps off? Yes
GO to
Q2 .
No
REPAIR Circuit 478 (TN/OG). TEST the system
for normal operation. Q2 CHECK FOG LAMP RELAY
z
Check the fog lamp relay; refer to
Wiring Diagrams Cell 149.
z Is the fog lamp relay OK? Yes
RECONNECT the fog lamp relay. GO to
Q3 .
No
INSTALL a new fog lamp relay. TEST the system
for normal operation. Q3 CHECK FOG LAMP SWITCH
z
Disconnect: Fog Lamp Switch C240.
z Are the fog lamps off? Yes
INSTALL a new fog lamp switch. TEST the
system for normal operation.
No
REPAIR Circuit 188 (WH/BK) for short. TEST the
system for normal operation. Klj . 5 ba
62003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...

Pinpoint Tests
PINPOINT TEST R: THE REVERSING LAMPS ARE INOPERATIVE z
The individual reversing lamp
is inoperative z
Bulb.
z Circuitry. z
GO to Pinpoint Test S .
z The reversing lamps are on
continuously z
Circuitry.
z DTR sensor (A/T).
z Reversing lamp
switch (M/T). z
GO to Pinpoint Test T .
Test Step Result / Action to Take
R1 CHECK THE VOLTAGE TO THE DTR SENSOR (A/T) OR
THE REVERSING LAMP SWITCH (M/T) z
Key in OFF position.
z Disconnect: DTR Sensor C167 (A/T).
z Disconnect: Reversing Lamp Switch C169 (M/T).
z Key in ON position.
z If equipped with A/T, measure the voltage between DTR
sensor C167 Pin 9, Circuit 1087 (OG), harness side and
ground.
z If equipped with M/T, measure the voltage between
reversing lamp switch C169, Circuit 1087 (OG), harness
side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
R2 .
No
REPAIR the circuit. TEST the
system for normal operation. R2 CHECK CIRCUIT 140 (BK/PK) FOR OPEN
z
Key in OFF position.
z If equipped with A/T, measure the resistance between
DTR sensor C167 Pin 11, Circuit 140 (BK/PK), harness
side and ground. Yes
INSTALL a new DTR sensor
(A/T) or reversing lamp switch
(M/T); REFER to
Section 307 -
01 ,
Section 308 - 03A or
Section 308 - 03B . TEST the Klj . 2 ba
42003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_5108/S3B~us~en~ ...