pinpoint FORD MUSTANG 2003 Workshop Manual

PINPOINT TEST F: NO OPERATION IN ALL TEMPERATURE
SETTINGS
PINPOINT TEST G: THE BLOWER MOTOR DOES NOT
OPERATE/DOES NOT OPERATE CORRECTLY INSTALL a new A/C
compressor due to low
performance. REFER to
Section 412
- 03 . TEST the
system for normal operation. Test Step Result / Action to Take
F1 CHECK THE TEMPERATURE CONTROL
z
Start the engine and run at idle. Allow the engine to reach
normal operating temperature.
z Place the function selector switch in the NORMAL A/C
position.
z Adjust the temperature control to full warm position, and
physically feel the discharge air temperature at the at the
center panel vents.
z Rotate the temperature control to full cold position, and
physically feel the discharge air temperature at the center
panel vents.
z Does the discharge air temperature vary? Yes
The temperature blend
door is functioning
correctly. RETURN to the
symptom chart.
No
GO to
F2 .
F2 CHECK FOR A BROKEN A/C TEMPERATURE CONTROL
CABLE z
Remove the climate control assembly to gain access to the
control cable head.
z Move the temperature control from full warm to full cold.
z Inspect the cable control head as you move the temperature
control.
z Does the alignment mark on the control head move? Yes
INSTALL a new
evaporator housing.
REFER to
Section 412 -
02 .
No
INSTALL a new
temperature control cable
assembly. REFER to
Section 412 - 04 .
Test Step Result / Action to Take
G1 CHECK FOR VOLTAGE AT C238
z
Disconnect: Blower Motor Jumper C238.
z Key in ON position.
z Turn the blower motor selector to LOW.
z Turn the function selector to FLOOR.
z Check for voltage between C238- 6, circuit 249 (DB/LG) and
C238- 3, circuit 261 (OG/BK). Yes
GO to
G2 .
No
GO to G4 . Klj . 30 ba
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PINPOINT TEST H: THE BLOWER MOTOR OPERATES
CONTINUOUSLY IN HIGH SPEED z
Check the resistance between C294a- 3, circuit 1205 (B/K)
harness side and ground.
z Is the resistance less than 5 ohms? Test Step Result / Action to Take
H1 CHECK THE FUNCTION SELECTOR SWITCH
z
Key in ON position.
z Set the blower motor speed to low.
z Check for blower motor operation in each function
selector switch position.
z Does the blower motor operate on high in all of
the function selector positions? Yes
GO to
H2 .
No
If the blower motor operates in the
OFF position, GO to H4 .
H2 CHECK CIRCUIT 261 (OG/BK) FOR A SHORT TO
GROUND z
Key in OFF position.
z Disconnect: A/C Blower Motor C2066.
z Disconnect: Blower Motor Resistor C2185.
z Disconnect: Blower Motor Switch C294a.
z Measure the resistance between C2066 circuit 261
(OG/BK), and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
H3 .
No
REPAIR circuit 261 (OG/BK) for a
short to ground. TEST the system
for normal operation. H3 CHECK THE BLOWER MOTOR SWITCH
OPERATION z
Measure the resistance of the blower motor switch.
Refer to the chart shown.
Blower Motor Switch Test Switch
Position Conductivity Between
Terminals Yes
INSTALL a new heater blower
motor switch resistor. REFER to
Section 412
- 04 . TEST the
system for normal operation.
No Klj . 34 ba
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PINPOINT TEST I: NO OPERATION IN HIGH BLOWER SETTING z
Is the resistance less than 5 ohms? Low None
Medium/low 2 and 3 only
Medium/high 2, 3 and 4 only
High 1, 2 and 4 only INSTALL a new heater blower
motor switch. REFER to
Section 412 - 04 . TEST the system for
normal operation. H4 CHECK THE FUNCTION SELECT SWITCH FOR A
SHORT TO BATTERY z
Key in OFF position.
z Disconnect: Function Selector Switch C294c.
z Key in ON position.
z Did the blower motor stop operating? Yes
INSTALL a new function selector
switch. REFER to
Section 412 -
04 . TEST the system for normal
operation.
No
REPAIR circuit 249 (DB/LG) for a
short to battery. TEST the system
for normal operation. Test Step Result / Action to Take
I1 CHECK CIRCUIT 261 (OG/BK) FOR AN OPEN CIRCUIT
z
Key in OFF position.
z Disconnect: Blower Motor Switch C294a.
z Key in ON position.
z Turn the function selector switch to the FLOOR position.
z Measure the voltage between blower motor switch C294a,
circuit 261 (OG/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
I2 .
No
REPAIR circuit 261 (OG/BK)
for an open circuit. TEST the
system for normal operation. I2 CHECK CIRCUIT 1205 (BK) FOR AN OPEN Klj . 35 ba
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PINPOINT TEST J: NO OPERATION IN LOWER SPEEDS
Component Tests z
Measure the resistance between C294a- 3, circuit 1205
(BK), harness side and ground.
z Is the resistance less than 10,000 ohms? Yes
REPAIR circuit 1205 (BK) for
an open. TEST the system for
normal operation.
No
INSTALL a new blower motor
switch. REFER to
Section 412 - 04 . TEST the system for
normal operation. Test Step Result / Action to Take
J1 CHECK CIRCUIT 261 (OG/BK) FOR AN OPEN
z
Disconnect: Blower Motor Resistor C294a.
z Key in ON position.
z Turn the function selector switch to the FLOOR position.
z Set the blower motor switch to low.
z Measure the voltage between the blower motor resistor
C2185- 4, circuit 261 (OG/BK), jumper side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
J2 .
No
REPAIR circuit 261 (OG/BK) for
an open circuit between the
blower motor and the blower
motor resistor. TEST the
system for normal operation. J2 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between the blower motor
resistor C2185- 1, circuit 1205 (BK), jumper side and
ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new blower motor
resistor. REFER to
Section 412 -
03 . TEST the system for
normal operation.
No
REPAIR circuit 1205 (BK) for an
open between the blower motor
resistor and ground. TEST the
system for normal operation. Klj . 36 ba
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GENERAL PROCEDURES
Tracer Dye Leak Detection
NOTE:
Ford Motor Company vehicles are produced with a permanent leak tracer dye incorporated into
the A/C system. The location of leaks can be pinpointed by the bright yellow- green glow of the tracer
dye. Since more than one leak can exist, always inspect each component.
1. Check for leaks using a 120 Watt UV spot lamp. zScan all components, fittings and lines of the A/C system.
2. After the leak is repaired, remove any traces of tracer dye with a general purpose oil solvent.
3. Verify the repair by operating the system for a short time and inspect with the UV spot lamp.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
120 Watt 110 Volt UV Lamp
20°C
164-
R0721 or equivalent Klj . 1 ba
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DIAGNOSIS AND TESTING
Instrument Cluster and Panel Illumination
Refer to Wiring Diagrams Cell
71 , Instrument Illumination for schematic and connector information.
Inspection and Verification
NOTE: A new instrument cluster must be reconfigured. Refer to Section 418 - 01 .
NOTE: The instrument panel dimmer switch is a part of the headlamp switch.
1. Verify the customer concern.
2. Visually inspect for obvious signs of electrical damage.
3. If the fault is not visually evident, determine the symptom and proceed to the Symptom Chart.
Symptom Chart SECTION 413-
00: Instrument Cluster and Panel Illumination 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent
Visual Inspection Chart Electrical
z
Central junction box (CJB) fuses:
„5 (15A)
„ 21 (5A)
„ 34 (20A)
„ 37 (5A)
„ 32 (15A)
„ 27 (20A)
z Circuitry
z Damaged switch
Symptom Chart Condition
Possible Sources Action
z The control illumination is
inoperative z
Central junction box
(CJB) fuse 37 (5A).
z Circuitry.
z Headlamp switch. z
Go To Pinpoint Test A .
z The instrument cluster
illumination is inoperative z
Circuitry.
z Instrument cluster. z
Go To Pinpoint Test B . Klj . 1 ba
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Pinpoint Tests
PINPOINT TEST A: THE CONTROL ILLUMINATION IS INOPERATIVE
PINPOINT TEST B: THE INSTRUMENT CLUSTER ILLUMINATION IS
INOPERATIVE z
Bulb(s).
z The climate control
illumination is inoperative z
Circuitry.
z Bulb(s). z
Go To Pinpoint Test C .
z The audio system
illumination is inoperative z
Circuitry.
z Audio unit. z
Go To Pinpoint Test D .
z A single illumination source
is inoperative z
Circuitry.
z Switch. z
Go To Pinpoint Test E .
Test Step Result / Action to Take
A1 CHECK PARKING LAMPS
z
Place the headlamp switch in the ON
position.
z Are the exterior lamps on? Yes
Place the headlamp switch in the OFF position.
GO to
A2 .
No
REFER to Section 417 - 01 .
A2 CHECK HEADLAMP SWITCH
z
Key in OFF position.
z Carry out the headlamp switch
components test;
Refer to Wiring Diagrams Cell 149 for
schematic and connector information.
.
z Is the headlamp switch OK? Yes
RECONNECT the headlamp switch. GO to
A3 .
No
INSTALL a new headlamp switch. REFER to
Section 417 - 01 . TEST the system for normal
operation. A3 CHECK CIRCUIT 1045 (DB/WH)
z
Place the headlamp switch in the ON
position.
z Rotate the instrument panel dimmer
switch to the full illumination position.
z Measure voltage between central
junction box (CJB) fuse 37 (5A) and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR circuit 19 (LB/RD). TEST the system for
normal operation.
No
REPAIR circuit 1045 (DB/WH). TEST the system
for normal operation.
Test Step Result / Action to Take
B1 CHECK VOLTAGE TO INSTRUMENT CLUSTER
ILLUMINATION z
Disconnect: Instrument Cluster .
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the full Yes
GO to
B2 . Klj . 2 ba
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PINPOINT TEST C: THE CLIMATE CONTROL ILLUMINATION IS
INOPERATIVE illumination position.
z Measure the voltage between the instrument cluster C220b
pin 4, circuit 19 (LB/RD), harness side and ground.
z Is the voltage greater than 10 volts? No
REPAIR the circuit. TEST
the system for normal
operation.
B2 CHECK GROUND TO INSTRUMENT CLUSTER
z
Place the headlamp switch in the OFF position.
z Measure the resistance between the instrument cluster
C220b pin 1, circuit 1205 (BK), harness side and ground.
z Are the resistances less than 5 ohms? Yes
INSTALL a new instrument
cluster. REFER to
Section 413 - 01 . TEST the system
for normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation. Test Step Result / Action to Take
C1 CHECK VOLTAGE TO CLIMATE CONTROL ILLUMINATION
z
Disconnect: Function Selector Switch C294b .
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the full
illumination position.
z Measure the voltage between the function selector switch
C294b pin 2, circuit 19 (LB/RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
C2 .
No
REPAIR the circuit.
TEST the system for
normal operation. C2 CHECK GROUND TO CLIMATE CONTROL Klj . 3 ba
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PINPOINT TEST D: THE AUDIO SYSTEM ILLUMINATION IS
INOPERATIVE z
Measure the resistance between the function selector switch
C294b pin 1, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL new
illumination bulb(s).
REFER to
Section 412 -
04 .
No
REPAIR the circuit.
TEST the system for
normal operation. Test Step Result / Action to Take
D1 CHECK VOLTAGE TO AUDIO UNIT
z
Disconnect: Audio Unit C290a.
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the full
illumination position.
z Measure the voltage between the audio unit C290a pin
1, circuit 19 (LB/RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
D2 .
No
REPAIR the circuit. TEST the
system for normal operation. D2 CHECK GROUND TO AUDIO UNIT
z
Measure the resistance between the audio unit C290a
pin 2, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
REMOVE the audio unit and
SEND it to an authorized Ford
audio systems repair facility.
TEST the system for normal
operation.
No
REPAIR the circuit. TEST the
system for normal operation. Klj . 4 ba
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PINPOINT TEST E: A SINGLE ILLUMINATION SOURCE IS
INOPERATIVE
Test Step Result / Action to Take
E1 CHECK VOLTAGE TO THE SINGLE
ILLUMINATION SOURCE z
Disconnect: Inoperative Illumination Source.
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the
full illumination position.
z Measure the voltage between the inoperative
illumination source, circuit 19 (LB/RD), harness
side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
E2 .
No
REPAIR the circuit. TEST the system
for normal operation. E2 CHECK SINGLE ILLUMINATION SOURCE
GROUND z
Measure the resistance between inoperative
illumination source, circuit 1205 (BK), harness side
and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new component in
question. TEST the system for normal
operation.
No
REPAIR the circuit. TEST the system
for normal operation. Klj . 5 ba
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