2003 FORD MUSTANG relay

Output Shaft Speed (OSS) Sensor Harness Connector 1 — NOT USED
2 — Signal Return
3 — TR3A
4 — TR1
5 — TR2
6 — TR4
7 — NOT USED
8 — NOT USED
9 — Fused Power Feed
10 — Starter Control
11 — Reverse
12 — Starter to Starter Interrupt Relay
Pin Number Circuit Circuit Function
1 — Output Shaft Speed (OSS) Sensor
2 — Signal Return
Digital Transmission Range (TR) Sensor Diagnosis Chart Selector Position PID: TR PID: TR_D PID: TR_V (volts)
TR4 TR3A TR2 TR1 TR3A (PCM Pin 64 to sigrtn)
PARK P/N 0 0 0 0 0.0 Volts
In Between REV 0 1 0 0 1.3 -
1.8 Volts REVERSE REV 1 1 0 0 1.3 -
1.8 Volts In Between REV 0 1 0 0 1.3 -
1.8 Volts NEUTRAL NTRL 0 1 1 0 1.3 -
1.8 Volts In Between
O/D
a 1 1 1 0 1.3 -
1.8 Volts OVERDRIVE
O/D
a 1 1 1 1 1.3 -
1.8 Volts In Between Man 2 1 0 1 1 0.0 Volts Klj . 3 ba
42003 Mustang Workshop Manual
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The clutch control system engages and disengages the clutch. The clutch control system disengages
the clutch when the clutch pedal is depressed and engages the clutch when the clutch pedal is
released. Clutch pedal motion is transmitted by the clutch release lever cable to the clutch release
lever. The clutch release hub and bearing engages the clutch pressure plate diaphragm spring,
releasing the pressure on the clutch disc which in turn disengages the transmission from the engine.
The clutch adjusts automatically to compensate for clutch disc wear. The clutch linkage is self-
adjusting.
The clutch pedal position (CPP) switch prevents the starter motor from engaging unless the clutch
pedal is depressed all the way to the floor. The switch plunger is contacted by the clutch pedal and
extends as the clutch pedal is pressed. The clutch pedal position switch is electrically connected in line
with the ignition switch and the starter motor relay coil. The CPP also turns off the speed control when
the clutch pedal is depressed. 4 7L583 Clutch pedal quadrant and pawl assembly Klj . 2 ba
22003 Mustang Workshop Manual
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If two substances of different temperature are placed near each other, the heat in the warmer
substance will transfer to the colder substance.
Latent Heat of Vaporization
When a liquid boils (converts to a gas), it absorbs heat without raising the temperature of the resulting
gas. When the gas condenses (reverts back to a liquid), it gives off heat without lowering the
temperature of the resulting liquid.
Relative Humidity
The amount of moisture (water vapor content) that the air can hold is directly related to the air
temperature. The more heat there is in the air, the more moisture the air can hold. The lower the
moisture content in the air, the more comfortable you feel. Removing moisture from the air lowers its
relative humidity and improves personal comfort.
Effects of Pressure on Boiling or Condensation
As the pressure is increased on a liquid, the temperature at which the liquid boils (converts to a gas)
also increases. Conversely, when the pressure on a liquid is reduced, its boiling point is also reduced.
When in the gas state, an increase in pressure causes an increase in temperature, while a decrease in
pressure will decrease the temperature of the gas.
Compressor Anti-
Slugging Strategy
Liquid refrigerant may accumulate in the A/C compressor under certain conditions. To alleviate
damage to the A/C compressor, compressor anti- slugging strategy (CASS) is utilized.
CASS is initiated only under specific conditions:
zthe ignition is off for more than 8 hours
z the ambient temperature is above -4º C (25ºF)
z battery voltage is above 8.5 volts during engine cranking
When these conditions are present, the powertrain control module (PCM) will activate the A/C control
relay prior to cranking of the engine. The A/C control relay engages the A/C compressor for
approximately 4- 15 A/C compressor revolutions or a maximum of 2 seconds (depending upon vehicle
application), allowing the liquid refrigerant to be pushed from the A/C compressor. CASS is initiated by
the PCM regardless of the function selector switch position or the EATC system settings.
The Refrigerant Cycle
During stabilized conditions (air conditioning system shut down), the refrigerant is in a vaporized state
and pressures are equal throughout the system. When the A/C compressor (19703) is in operation, it
increases pressure on the refrigerant vapor, raising its temperature. The high- pressure and high-
temperature vapor is then released into the top of the A/C condenser core (19712).
The A/C condenser core, being close to ambient temperature, causes the refrigerant vapor to
condense into a liquid when heat is removed from the refrigerant by ambient air passing over the fins
and tubing. The now liquid refrigerant, still at high pressure, exits from the bottom of the A/C
condenser core and enters the inlet side of the A/C evaporator core orifice (19D990).
The A/C evaporator core orifice is the restriction in the refrigerant system that creates the high
pressure buildup upstream of the A/C evaporator core (19860) and separates the high and low
pressure sides of the A/C system. As the liquid refrigerant leaves this restriction, its pressure and
boiling point are reduced.
The liquid refrigerant is now at its lowest pressure and temperature. As it passes through the A/C Klj . 3 ba
112003 Mustang Workshop Manual
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Item Part Number Description
1 19980 Manual A/C control assembly
2 19E561 A/C cycling switch
3 19D594 A/C pressure cutoff switch (V6)
4 19D594 A/C pressure cutoff switch (V8)
5 12A650 Powertrain control module
6 12B581 Constant control relay module
7 19703 A/C compressor
8 19805 Blower motor Klj . 10 ba
112003 Mustang Workshop Manual
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Symptom Chart
Condition
Possible Sources Action
z Incorrect/erratic direction
of airflow from outlet(s) z
No vacuum to A/C heater
function switch selector.
z A/C heater function selector
switch leaks vacuum.
z Kinked/pinched vacuum hose.
z Leaking vacuum control
motor.
z Leaking A/C vacuum check
valve.
z Leaking A/C vacuum reservoir
tank and bracket.
z Vacuum actuator arm not
connected to door crank. z
Go To Pinpoint
Test A .
z Insufficient, erratic, or no
heat z
Low engine coolant level.
z Thermostat stuck open.
z Disengaged/damaged
temperature cable. z
Go To Pinpoint
Test B .
z The A/C does not
operate/does not operate
correctly z
CASS strategy failure.
z Open fuses.
z A/C clutch relay.
z Shorted blend door actuator.
z Powertrain control module.
z Circuitry short/open.
z A/C cycling switch damaged.
z A/C system discharged/low
charge.
z Function selector switch
damaged.
z A/C pressure cut-off switch
damaged.
z A/C compressor clutch
damaged. z
Go To Pinpoint
Test C .
z The A/C is always on zCircuitry short/open.
z A/C cycling switch.
z A/C heater function selector
switch.
z Constant control relay
module.
z Incorrect A/C clutch air gap. z
Go To Pinpoint
Test D .
z Insufficient A/C cooling zRestricted A/C evaporator
core orifice.
z Low refrigerant level. z
Go To Pinpoint
Test E .
z No operation in all the
temperature settings z
Damaged blend door actuator
cable.
z Damaged air temperature
control door. z
Go To Pinpoint
Test F .
z The blower motor does
not operate z
Open fuse.
z Circuitry open/shorted.
z Damaged heater blower
motor switch (18578).
z Damaged heater blower
motor switch resistor (18591).
z Damaged blower motor relay.
z Damaged blower motor. z
Go To Pinpoint
Test G .
z The blower motor
operates continuously in z
Circuitry short/open.
z Damaged heater blower z
Go To Pinpoint Klj . 6 ba
412003 Mustang Workshop Manual
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z
Is the voltage reading greater than 10 volts? C18 CHECK THE A/C CYCLING SWITCH
z
Key in OFF position.
z Disconnect: A/C Cycling Switch C130.
z NOTE: The A/C pressure cut- off switch C1078 for the
3.8L engine is shown, C1078 for the 4.6L engines is
similar. The pin locations and the circuits are identical.
z Measure the resistance between A/C cycling switch
C130- 2, circuit 420 (DB/YE), harness side and the A/C
high pressure cut- off switch C1078-2, circuit 420
(DB/YE), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new A/C cycling
switch. REFER to
Section 412 -
03 . TEST the system for
normal operation.
No
REPAIR circuit 420 (DB/YE) for
an open. TEST the system for
normal operation. C19 CHECK THE A/C PRESSURE CUT-
OFF SWITCH z
Key in OFF position.
z NOTE: The A/C pressure cut- off switch C1078 for the
3.8L engine is shown, C1078 for the 4.6L engines is
similar. The pin locations and the circuits are identical.
z Measure the resistance between Rotunda Breakout Box
pin 41 and A/C high pressure cut- off switch C1078-3,
circuit 198 (DG/OG), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new A/C pressure
cut-
off switch. REFER to
Section 412 - 03 . TEST the
system for normal operation.
No
REPAIR circuit 198 (DG/OG)
for an open. TEST the system
for normal operation. C20 CHECK THE GROUND CIRCUIT AT THE CONSTANT
CONTROL RELAY MODULE z
Key in OFF position. Yes Klj . 21 ba
412003 Mustang Workshop Manual
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z
Disconnect: CCRM C1262.
z Measure the resistance of CCRM C1262- 18, circuit 1205
(BK), harness side and ground.
z Is the resistance reading less than 5 ohms? GO to
C21 .
No
REPAIR circuit 1205 (BK) for
an open. TEST the system for
normal operation. C21 CHECK CIRCUIT 20 (WH/LB) AT THE CONSTANT
CONTROL RELAY MODULE z
Key in ON position.
z Measure the voltage at the CCRM C1262- 13, circuit 20
(WH/LB), harness side and ground.
z Is the voltage reading greater than 10 volts? Yes
GO to
C22 .
No
REPAIR circuit 20 (WH/LB) for
an open. TEST the system for
normal operation. C22 CHECK THE POWER TO THE A/C CLUTCH
z
Key in OFF position.
z Connect: CCRM 1262.
z Disconnect: A/C Clutch C100.
z Turn the function selector to the A/C position.
z Measure the voltage at the A/C clutch C100, circuit 347
(BK/YE), harness side and ground. Yes
GO to
C24 .
No
GO to C23 . Klj . 22 ba
412003 Mustang Workshop Manual
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z
Is the voltage greater than 10 volts? C23 CHECK CIRCUIT 331 (PK/YE) FOR AN OPEN.
z
Key in OFF position.
z Disconnect: CCRM C1262.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool:
z In the Active Command Mode command the PCM
outputs ON.
z Measure the resistance between the CCRM C1262- 22,
circuit 331 (PK/YE), harness side and ground.
z Is the resistance reading less than 5 ohms? Yes
GO to
C24 .
No
REPAIR circuit 331 (PK/YE) for
an open. TEST the system for
normal operation. C24 CHECK CIRCUIT 347 (BK/YE)
z
Key in OFF position.
z Measure the resistance between CCRM C1262- 23,
circuit 347 (BK/YE), harness side and A/C clutch C100-
1, harness side.
z Is the resistance less than 5 ohms? Yes
GO to
C25 .
No
REPAIR circuit 347 (BK/YE) for
an open. TEST the system for
normal operation. C25 CHECK CIRCUIT 347 (BK/YE) FOR A SHORT TO
GROUND. z
Measure the resistance between A/C clutch C100- 2,
circuit 1205 (BK), harness side and the CCRM C1262-
16, circuit 1205 (BK) harness side. Yes
INSTALL a new constant
control relay module. TEST the
system for normal operation. Klj . 23 ba
412003 Mustang Workshop Manual
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