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1995 Lincoln Town Car 4.6L Eng Signature
A/C-HEATER SYSTEM
ADJUSTMENTS > TEMPERATURE BLEND DOOR ACTUATOR
The temperature blend door is operated by an electric motor (actuator). The actuator has an automatic
recalibration feature that can be activated by disconnecting the positive battery cable for at least 30
seconds. When the battery cable is reconnected, the A/C system will automatically recalibrate.
TROUBLE SHOOTING > SELF-DIAGNOSTIC TEST > ENTERING SELF-DIAGNOSTICS &
RETRIEVING CODES
1. Ensure temperature of air inside vehicle is 60-80°F (16-27°C). If temperature is not as specified,
the system will falsely indicate that the in-car temperature sensor is faulty by displaying codes.
Turn ignition on. Simultaneously press OFF and FLOOR buttons, then press AUTOMATIC button
within 2 seconds. Wait at least 30 second for the self-test to run (during this time, the display will
be blank).
2. If display is blank for longer than 30 seconds, or if Code 888 is displayed, go to TEST "A" (EATC
SYSTEM TEST). If codes are displayed, record code numbers. Repair codes in the order they are
displayed. See SELF-DIAGNOSTIC CODE table.
CAUTION: Before turning ignition off, exit
self-diagnostics.
TROUBLE SHOOTING > SELF-DIAGNOSTIC TEST > EXITING SELF-DIAGNOSTICS
WITHOUT CLEARING CODES
Press COOL (Blue) button.
TROUBLE SHOOTING > SELF-DIAGNOSTIC TEST > EXITING SELF-DIAGNOSTICS &
CLEARING CODES
Press defrost button.
SELF-DIAGNOSTIC CODE
Code Number
024, 025
(1)
Circuit Test
Perform
Temp. Blend Door Actuator
"B"
030
In-Car Sensor Shorted
"P"
031
In-Car Sensor Open
"P"
040, 042
(1)
Ambient Sensor Shorted
"J"
041, 043
(1)
Ambient Sensor Open
"J"
050, 052
(1)
Sunload Sensor Shorted
"K"
115
(1)
Engine Coolant Temp. Sensor
"G" Or "H"
125
(1)
Vehicle Speed Sensor
"G" Or "H"
888
(1)
No Fault Found
"A"
Intermittent fault.
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(1)
Intermittent fault.
TROUBLE SHOOTING > TEST B - TEMP. BLEND DOOR ACTUATOR
Question: Misprint in test?
1. Enter self-diagnostics, record any codes (if displayed), then exit self-diagnostics. See SELFDIAGNOSTIC TEST . If Code 020 or 021 is set, go to next step. If Code 020 or 021 is not set,
check for other codes. If any other codes are set, repair fault. If no other codes are set, perform
TEST A (EATC SYSTEM TEST).
2. Unplug both connectors from EATC module on back of control panel. Turn ignition on. Connect
one end of a jumper wire to terminal No. 24 (Black wire) of EATC module Black connector.
Momentarily connect other end of same jumper wire to terminal No. 22 (Purple wire), and then to
terminal No. 21 (Brown/Light Green wire). Motor should operate in both directions. If motor
operates as specified, go to next step. If motor does not operate as specified, go to step 6).
3. Reconnect wiring harness to EATC module. Perform TEST A (EATC SYSTEM TEST). If TEST A
does not reveal any problems, system is okay at this time. If TEST A reveals problems, go to next
step.
4. Operate motor until temperature blend door is in full heat position (if necessary, use procedure in
step 2). Turn ignition off. At White connector of EATC module, measure resistance between
specified terminals. See POSITION SENSOR RESISTANCE TEST table. If resistance is as
specified, go to next step. If resistance is not as specified, go to step 6).
POSITION SENSOR RESISTANCE TEST
Terminals No. (Wire Colors)
Ohms
15 & 6 (Red/Light Green & Red/White)
5000-7000
5 & 6 (Yellow/Light Green & Red/White)
3500-6000
5 & 15 (Yellow/Light Green & Red/Light Green)
250-1500
5. Reconnect EATC module harness connectors. Enter self-diagnostics, record any codes (if
displayed), then exit self-diagnostics. See SELF-DIAGNOSTIC TEST . If no codes are set, system
is okay at this time. If codes are set, return to step 1).
6. Turn ignition off. Inspect for open wiring between EATC module and actuator. If wiring is okay,
temporarily substitute known-good actuator, then go to next step. If wiring is open, repair and then
go to next step.
7. Reconnect wiring harness. Enter self-diagnostics, record any codes (if displayed), then exit selfdiagnostics. See SELF-DIAGNOSTIC TEST . If no codes are set, system is okay at this time. If
codes are set, return to step 1).
TESTING > A/C SYSTEM PERFORMANCE
1. Park vehicle out of direct sunlight. Connect manifold gauge set. Operate engine at 1500 RPM. Set
A/C controls to recirculated air, panel (vent) mode, and maximum cooling. Set function control
switch to MAX A/C.
2. Set blower/fan to high speed. Close doors and windows. Insert thermometer into center vent.
Operate system for 10-15 minutes to allow system to stabilize. Measure discharge air temperature.
3. Temperature must be 33-47°F (0.6-8°C) at center vent, with high side and low side pressures
within specification. See A/C SYSTEM HIGH SIDE PRESSURE SPECIFICATIONS table. Low side
pressure should remain at 25-45 psi (1.8-3.2 kg/cm2 ) throughout normal operating range.
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pressure should remain at 25-45 psi (1.8-3.2 kg/cm2 ) throughout normal operating range.
A/C SYSTEM HIGH SIDE PRESSURE SPECIFICATIONS
Ambient Temp. °F (°C)
psi (kg/cm2 )
60 (16)
75-175 (5.3-12.3)
70 (21)
100-200 (7-14)
80 (27)
125-230 (8.8-16.2)
90 (32)
150-260 (10.5-18.3)
REMOVAL & INSTALLATION
WARNING: To avoid injury from accidental air
bag deployment, read and carefully follow all
SERVICE PRECAUTIONS and DISABLING &
ACTIVATING AIR BAG SYSTEM procedures in the
AIR BAG RESTRAINT SYSTEM article in the
ACCESSORIES/SAFETY EQUIPMENT section.
REMOVAL & INSTALLATION > PLENUM & HEATER CORE > REMOVAL & INSTALLATION
1. Disconnect negative battery cable. Disconnect heater hoses from heater core tubes. Plug heater
hoses and heater core tubes.
2. Remove 3 nuts (below windshield wiper motor) attaching left side of plenum to dash panel.
Remove nut retaining upper left corner of evaporator case to dash panel. Remove left and right
lower instrument panel insulators.
3. Disconnect control system vacuum supply hose from vacuum source. Push grommet and vacuum
supply hose into passenger compartment. Remove 3 glove box hinge screws. Disconnect check
arms, and remove glove box.
4. Loosen right door sill plate. Remove right side of instrument panel to side cowl. Remove bolt
attaching lower right side of instrument panel to side cowl. Remove instrument panel pad.
5. Disconnect vacuum harness at multiple vacuum connector, near floor air-distribution duct.
Disconnect White vacuum hose from outside/recirculated air door vacuum motor.
6. Remove screws attaching passenger side of floor air-distribution duct to plenum. If necessary,
remove screws attaching partial (lower) panel door vacuum motor to mounting bracket for access
to right screw.
7. Remove plastic push-fastener retaining floor air-distribution duct to left of plenum. Remove screws
on rear face of plenum. Remove floor air-distribution duct.
8. Remove nuts from studs along lower flange of plenum. Carefully move plenum rearward to allow
heater core tubes and stud at top of plenum to clear holes in dash panel. Remove plenum from
vehicle by rotating top of plenum forward and then down and out from under instrument panel.
Complete removal by carefully pulling rearward as necessary while rolling plenum from behind
instrument panel.
9. Remove screws from heater core cover, then remove cover from plenum assembly. Pull heater
core and seal from plenum assembly. See Fig 1. To install, reverse removal procedure.
Fig 1: Exploded View Of Plenum Components
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Fig 1: Exploded View Of Plenum Components
Courtesy of FORD MOTOR CO.
REMOVAL & INSTALLATION > TEMPERATURE BLEND DOOR ACTUATOR > REMOVAL
Disconnect negative battery cable. Remove instrument panel. See INSTRUMENT PANEL . Locate blend
door actuator on upper evaporator case. Remove electrical connection and screws. Pull blend door actuator
from evaporator case.
REMOVAL & INSTALLATION > TEMPERATURE BLEND DOOR ACTUATOR >
INSTALLATION
To install, reverse removal procedure. After replacement is complete, blend door actuator must be
calibrated by disconnecting positive battery cable for at least 30 seconds. When positive battery cable is
reconnected, A/C system will automatically calibrate.
WIRING DIAGRAM
Fig 1: Automatic A/C-Heater System Wiring Diagram
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Fig 1: Automatic A/C-Heater System Wiring Diagram
3
YEL/LT GRN
4
RED/LT GRN
2
RED/WHT
6
BLK
HOT AT ALL TIMES
FUSE
7
15A
HOT AT ALL TIMES
I/P
FUSE
PANEL
FUSE
8
15A
ENGINE
COMPARTMENT
FUSE BOX
FUSE
P
30A
YEL
WHT/PPL
BRN/ORG
BLK
HOT IN RUN
FUSE
18
10A
LT GRN/PPL
BLK
HOT AT ALL TIMES
FUSE
1
15A
PPL/ORG
G203
(BEHIND RIGHT
COWL PANEL)
HOT IN RUN
FUSE
10
30A
LT BLU/PNK
HOT IN RUN
DK BLU 28
228
41
347
BLK/YEL
331
PNK/YEL 69
POWERTRAIN
CONTROL
MODULE
(LEFT REAR
OF ENGINE
COMPARTMENT, ON
SAFETY WALL)
YEL
BLK
BLK
M
MOTOR
CONTROL
8
PPL/ORG
1
BRN/LT GRN
5
G101
(FRONT OF RIGHT
FENDER APRON)
RED/ORG
M
COOLING
FAN
PCM
POWER
RELAY
PPL
RED
DK BLU
BLEND DOOR ACTUATOR
(BEHIND RIGHT SIDE OF
I/P, TOP OF
A/C PLENUM)
INTERIOR
LIGHTS
SYSTEM
767
AMBIENT TEMP INPUT
1
LT BLU/ORG
SENSOR GROUND
2
PNK/BLK
REDUN STR CTRL
3
BRN/LT BLU
ILLUMINATION
4
ORG/BLK
BLEND DOOR POT
5
YEL/LT GRN
BLEND DOOR REF
6
RED/WHT
438
BLOWER MOTOR SPEED
7
RED/PNK
756
BLEND DOOR REF
SUNLOAD SENS INPUT
IN CAR TEMP SENS
ILLUMINATION
470
BLK/YEL
1070
484
BLK
BLK
437
G104
(REAR OF
LEFT
FENDER
APRON)
436
15 RED/LT GRN
16 BRN
COOLING FAN
RELAY
(IN ENGINE COMPARTMENT FUSE BOX)
BLK/YEL
BLK
PPL
A/C CLUTCH
DIODE
PCM
POWER
RELAY
PPL
RED
PNK/YEL
468
A/C
COMPRESSOR
CLUTCH
790
17 WHT/ORG
19
18 LT BLU/RED
WOT CUTOUT
RELAY
(IN RELAY
CENTER)
19
ENG/MET CONV
20 RED 506
BLOWER SPPED FBACK
8
RED/WHT
757
BLW SPD OUTPUT
9
PPL/WHT
758
REDUN STR CTRL
10 ORG/LT BLU
BLK/YEL
1069
IGNITION
11 LT BLU/PNK
295
BATTERY
12 LT GRN/PPL
797
DATA LINK (-)
13 PNK/LT BLU
915
DATA LINK (+)
14 TAN/ORG
RED/YEL
PNK/LT BLU
914
BLEND DOOR ACT
21 BRN/LT GRN
BLEND DOOR ACT
22 PPL
TAN/ORG
9
2
245
A/C HIGH
PRESSURE
CUTOUT
SWITCH
(RIGHT SIDE
OF ENGINE
COMPARTMENT)
DATA LINK
CONNECTOR
(LEFT SIDE
OF I/P)
246
23
GROUND
A/C CLUTCH OUT
IGNITION
24 BLK
57
26 PPL/ORG
G203
(BEHIND RIGHT COWL PANEL)
883
25 PNK/LT BLU
RED/YEL
298
PNK/LT BLU
ELECTRONIC AUTOMATIC
TEMPERATURE
CONTROL MODULE
(CENTER OF I/P)
A/C LOW
PRESSURE
CUTOUT
SWITCH
(RIGHT REAR
OF ENGINE
COMPARTMENT)
G103
(RIGHT SIDE OF
ENGINE COMPARTMENT)
1 BLK
2 PPL/WHT
3 RED/PNK
4 ORG/RED
ON ACCUMULATOR)
5 RED/WHT
506
BLOWER MOTOR
SPEED CONTROLLER
(RIGHT REAR OF
ENGINE COMPARTMENT)
BLK
1
ENG/MET
INSTRUMENT
CLUSTER
(DIGITAL)
ORG/RED
M
NCA
ORG
RED
NCA
ELECTRONIC AUTOMATIC
TEMPERATURE CONTROL
BLOWER MOTOR
LT BLU/RED
1
1069
ORG/LT BLU
6
1070
BRN/LT BLU
7
WHT/PPL
9
595
NCA
BRN/ORG
NCA
296
NCA
AMBIENT
TEMPERATURE
SENSOR
(CENTER FRONT
OF ENGINE
COMPARTMENT)
IN-CAR
TEMPERATURE
SENSOR
(BEHIND TOP
CENTER
OF I/P)
EATC
SUNLOAD
SENSOR
(BELOW
RIGHT SIDE
OF I/P)
NCA
NCA
NCA
PNK/BLK
BRN
PNK/BLK
WHT/ORG
PNK/BLK
LT BLU/ORG
484
CLOCKSPRING
ASSEMBLY
(TOP OF
STEERING
COLUMN)
YEL
10
ORG/BLK
14
DK GRN/ORG
15
583
NCA
848
INTERIOR
LIGHTS
SYSTEM
SIGNAL
SIG GND
COM SIG
BAT
POWER
LED
RETURN
REDUNDANT
STEERING
CONTROL
MODULE
(CENTER OF I/P
ABOVE ASHTRAY)
AUDIO/CLIMATE
CONTROL
SWITCH
ASSEMBLY
64572
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