Chrysler New Yorker. Manual — part 332

heater A/C unit, is cooled to temperatures near the
freezing point. As warm damp air passes over the
fins in the evaporator, moisture in the air condenses
to water, dehumidifying the air. High humidity
reduces the evaporator’s ability to cool the air. Dur-
ing periods of high heat and humidity, an air condi-
tioning system will be less effective. With the control
module set to RECIRC, only air from the passenger
compartment passes through the evaporator. As the
passenger compartment air dehumidifies, A/C perfor-
mance levels rise.

PERFORMANCE TEST PROCEDURE

Review Safety Precautions and Warnings in this

group before proceeding with this procedure. Air tem-
perature in test room and in vehicle must be 21° C
(70°F) minimum for this test.

NOTE: When connecting the service equipment
coupling to the line fitting, verify that the valve of
the coupling is fully closed. This will reduce the
amount of effort required to make the connection.

(1) Connect a tachometer and manifold gauge set.

Attach a thermal couple to the evaporator line.

(2) Set controls:

MANUAL A/C

• A/C ON

• Panel Recirculation

• Temperature to full cold

• High blower

ATC (Automatic Temperature Control) System:

• Rotate blower knob to high position (full clockwise)

• Set temperature to the LO position

• Push panel mode button

• Push RECIRC (Recirculation) button (A/C and

RECIRC symbols should be lit)

NOTE: The word MANUAL should appear in the ATC
display, confirming that the system is set manually.

(3) Start engine and hold at 1000 rpm with A/C

clutch engaged.

(4) Engine should be warmed up with doors and

windows closed.

(5) Insert a thermometer in the left center A/C outlet

and operate the engine for five minutes. The A/C clutch
may cycle depending on ambient conditions.

(6) With the A/C clutch engaged, compare the

discharge air temperature to the A/C Performance
Temperature table.

ATC IN-CAR TEMPERATURE SENSOR

(1) Perform air flow test to check motor/fan assembly.

(a) Turn ignition to the ON position and push

the OFF button to stop the ATC system airflow.
This will make it easier to observe paper in the
step Step.

(b) Place a small piece of newspaper in front of

the sensor/motor opening on the ATC control. If the
paper sticks to the opening, the In-Car sensor/mo-
tor is operating properly. The piece of paper should
be only large enough to cover the grille opening.
(2) Check if the electrical connection and connector

are OK.

(3) Check for the two foam seals and their condition,

it is absolutely necessary for proper sensor operation.

(a) Seal on the inside surface directly behind the

nameplate.

(b) Seal (strip) located directly to the right of the

right center duct opening (instrument panels with
trim bezels).

A/C PERFORMANCE TEMPERATURE AND PRESSURE

AMBIENT TEMPERATURE

21°C

(70°F)

26.5°C

(80°F)

32.5°C

(90°F)

37°C

(100°F)

43°C

(110°F)

MAXIMUM ALLOWABLE AIR
TEMPERATURE AT CENTER
LEFT PANEL OUTLET

6°C

(42°F)

7°C

(45°F)

10°C

(50°F)

12°C

(54°F)

15°C

(59°F)

COMPRESSOR DISCHARGE
PRESSURE

1379–1585

kPa

(200–230

psi)

1448–1723

kPa

(210–250

psi)

1654–1930

kPa

(240–280

psi)

1930–2206

kPa

(280–320

psi)

2206–2516

kPa

(320–365 psi)

COMPRESSOR SUCTION
PRESSURE

103–172 kPa

(15–25 psi)

139–208 kPa

(20–30 psi)

172–241 kPa

(25–35 psi)

208–276 kPa

(30–40 psi)

241–310 kPa

(35–45 psi)

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HEATING AND AIR CONDITIONING

24 - 7

DIAGNOSIS AND TESTING (Continued)

SELF DIAGNOSTICS

DIAGNOSTIC TROUBLE CODES (DTC’s)

Both the ATC and the Manual A/C system are con-

trolled by the Body Control Module (BCM). Both sys-
tems can be diagnosed by the DRB scan tool or the
vehicles own control head display. Refer to the DRB
menu for checking Diagnostic Trouble Codes (DTC’s)
Note that there are three DTC tables. The ATC and
Manual A/C DTC table contain faults that are com-
mon to both the ATC and the Manual A/C system.
The same diagnosis can be used for both systems.
The DTC’s cover operation of the climate control unit
actuators,

doors,

evaporator

temperature

sensor,

ambient temperature sensor and the A/C refrigerant
system. The Manual A/C DTC table covers Fault
Codes that are for the manual A/C Control Head and
wiring and are not used on an ATC system. The ATC
DTC table has DTC’s for ATC Head Communications,
In-Car Temperature Sensor and Sun Sensor which
are not in a Manual A/C system.

TROUBLE CODES FROM THE ATC CONTROL

The trouble codes can be checked with the ATC

control if a DRB scan tool is not available. The con-
trol head can only be placed into the diagnostic mode
while the engine is running and the vehicle is not
moving. Set the control to a 75° F setting (so there is
no confusion with the 23-51 Diagnostic Trouble Codes
(DTC’s).

To place the system into it’s diagnostic mode, press

and hold the Floor, Mix and Defrost buttons (at the
same time). The ATC head display will begin to
blink. Release the Floor, Mix and Defrost buttons.
Once the control head enters the diagnostic mode,
the display on the control head will continue to blink.
This occurs until it completes its tests and climate
control unit door/actuator calibrations. Then it will
display any diagnostic trouble codes that are present
in the BCM. If there are no diagnostic trouble codes,
the system will return to its normal operation as
indicated by the temperature symbol (a C or a F).
Diagnostic trouble codes related to the ATC and cli-
mate control unit will appear on the display in
numerical form. The diagnostic trouble codes are
stored in the BCM and can range between 23 and 51.
The ATC control can only show one diagnostic trouble
code at a time. Under certain circumstances, more
than one diagnostic trouble code could be in the
memory. To scroll through any additional diagnostic
trouble codes, press the Panel Mode button on the
ATC control. It is important that no other knob
or button is pushed until all codes are read.
Pushing any button except Panel Mode or turn-
ing a knob will end the diagnostic test without
showing the rest of the trouble codes. There

ATC AND MANUAL A/C DTC’S

CODE

DESCRIPTION

23

BLEND DOOR ACTUATOR FEEDBACK
FAILURE

24

MODE DOOR ACTUATOR FEEDBACK
FAILURE

25

AMBIENT SENSOR

31

RECIRCULATION DOOR ACTUATOR
STALL FAILURE

32

BLEND DOOR ACTUATOR STALL
FAILURE

33

MODE FOOR ACTUATOR STALL
FAILURE

35

EVAPORATOR SENSOR FAILURE

37

BLEND DOOR ACTUATOR OUTPUT
SHORTED TO BATTERY

38

BLEND DOOR ACTUATOR OUTPUT
SHORTED TO GROUND

39

MODE DOOR ACTUATOR OUTPUT
SHORTED TO BATTERY

40

MODE DOOR ACTUATOR OUTPUT
SHORTED TO GROUND

41

RECIRC DOOR ACTUATOR OUPUT
SHORTED TO BATTERY

42

RECIRC DOOR ACTUATOR OUTPUT
SHORTED TO GROUND

43

COMMON DOOR OUTPUT SHORTED
TO BATTERY

44

COMMON DOOR OUTPUT SHORTED
TO GROUND

51

SYSTEM VOLTAGE TOO LOW FOR
DOOR CALIBRATION

MANUAL A/C DTC’S

CODE

DESCRIPTION

45

A/C CONTROL BLEND DOOR INPUT
OPEN OR SHORTED TO GROUND

46

A/C CONTROL BLEND DOOR
SHORTED TO BATTERY

47

A/C CONTROL - A/C SWITCH FAILURE

48

A/C CONTROL MODE DOOR INPUT
SHORTED TO GROUND

49

A/C CONTROL MODE DOOR INPUT
SHORTED TO BATTERY

50

A/C CONTROL ELECTRIC BACKLITE
(EBL) SWITCH FAILURE

24 - 8

HEATING AND AIR CONDITIONING

300M

DIAGNOSIS AND TESTING (Continued)

also may be other trouble codes stored in the
BCM not related to the Climate Control System.
These codes can only be found using the DRB
scan tool.

TROUBLE CODES FROM THE MANUAL A/C CONTROL

The trouble codes can be checked with the Manual

A/C

control

and

the

Odometer

Display

of

the

Mechanical Instrument Cluster of a DRB scan tool is
not available. The Manual A/C Control Head can only
be placed into the diagnostic mode while the engine
is running and the vehicle is not moving. To place
the system into it’s diagnostic mode, adjust the Man-
ual A/C Control to the following settings:

(1) The engine must be running with vehicle not

moving.

(2) The Fan Speed set to any speed except OFF.
(3) The Temperature Knob in full cold (full coun-

terclockwise position).

(4) The mode knob must be placed in defrost posi-

tion (full clockwise position).

(5) The A/C button can be ON or OFF.
(6) Press and hold the EBL button until the

Mechanical Instrument Cluster Odometer display
indicates an “AC00”. The body control module (BCM)
will chime once and the Manual A/C control A/C but-
ton LED will begin blinking.

(7) Release the EBL button and wait until the

Manual A/C Control A/C button LED stops blinking.
This means that the error check and climate control
unit door calibration is complete.

Diagnostic trouble codes related to the Manual A/C

Control and the climate control unit will appear on
the odometer display in numerical form after the let-
ters “AC”. The diagnostic trouble codes are stored in
the BCM and can range between 23 and 51. The
odometer display will return to normal operation if
no trouble codes are found. If a problem is found,
then the odometer will display the letters “A/C” fol-
lowed by the trouble code number. The odometer dis-
play can only show one diagnostic trouble code at a
time. Under certain circumstances, more than one
diagnostic trouble code could be in the memory. To
scroll through any additional diagnostic trouble
codes, press the A/C button on the Manual-A/C con-
trol. The BCM will beep each time the A/C button is
pushed. Continue pushing the A/C button and record-
ing the trouble code numbers until the odometer
returns to normal operation (note the letters AC will
disappear). It is important that no other knob or
button is pushed until all codes are read. Push-
ing any button except the A/C button or turning
a knob will end the diagnostic test without
showing the rest of the trouble codes. There
also may be other trouble codes stored in the
BCM not related to the Climate Control System.
These codes can only be found using the DRB
scan tool.

ATC DTC’S

CODE

DESCRIPTION

26

ATC IN-CAR TEMPERATURE
THERMISTER FAILURE

27

ATC IN-CAR SENSOR FAILURE

34

ENGINE TEMPERATURE MESSAGE
NOT RECEIVED

36

ATC CONTROL COMMUNICATION
FAILURE

Fig. 4 Entering Self-Diagnostic Mode

Fig. 5 Manual A/C Control Head

300M

HEATING AND AIR CONDITIONING

24 - 9

DIAGNOSIS AND TESTING (Continued)

ERASING DIAGNOSTIC TROUBLE CODES (DTC’s)

Diagnostic trouble codes can be cleared from the

memory two ways:

• The DRB scan tool

• Power to the BCM can be disconnected for ten

minutes

by

disconnecting

the

battery

negative

remote cable.

If the scan tool is to be used, refer to the proper

LH Body Diagnostic Procedures Manual.

CAUTION: Fault code 26 can be created if the
in-car sensor thermistor is disconnected while the
BCM is operating. This can happen by disconnect-
ing connectors from the BCM or the ATC Control
Head when the battery is connected (even if the
ignition switch is OFF). To correct, clear the fault
code 26 from the BCM.

HEATER PERFORMANCE TEST

PRE-DIAGNOSTIC PREPARATIONS

Review Safety Precautions and Warnings in this

group before performing the following procedures.

Check the coolant level, drive belt tension, vacuum line

connections, radiator air flow and fan operation. Start
engine and allow to warm up to normal temperature.

WARNING: DO

NOT

REMOVE

RADIATOR

CAP

WHEN ENGINE IS HOT, PERSONAL INJURY CAN
RESULT.

If vehicle has been run recently, wait 15 minutes

before removing cap. Place a rag over the cap and
turn it to the first safety stop. Allow pressure to
escape through the overflow tube. When the system
stabilizes, remove the cap completely.

MAXIMUM HEATER OUTPUT: TEST AND
ACTION

Engine coolant is provided to the heater system by

two 16 mm (5/8 inch inside diameter) heater hoses.
With engine idling at normal running temperature,
set the control to maximum heat, floor, and high
blower setting. Using a test thermometer, check the
air temperature coming from the floor outlets. Refer
to Temperature Reference Table.

If the floor outlet air temperature is insufficient,

refer to Group 7, Cooling Systems for specifications.
Both heater hoses should be HOT to the touch (cool-
ant return hose should be slightly cooler than the
supply hose). If coolant return hose is much cooler
than the supply hose, locate and repair engine cool-
ant flow obstruction in heater system.

POSSIBLE LOCATIONS OR CAUSE OF
OBSTRUCTED COOLANT FLOW

(1) Pinched or kinked heater hoses.
(2) Improper heater hose routing.
(3) Plugged heater hoses or supply and return

ports at cooling system connections, refer to Group 7,
Cooling System.

(4) Plugged heater core.
(5) Air locked heater core.
(6) If coolant flow is verified and outlet tempera-

ture is insufficient, a mechanical problem may exist.

POSSIBLE LOCATION OR CAUSE OF
INSUFFICIENT HEAT

(1) Obstructed cowl air intake.
(2) Obstructed heater system outlets.
(3) Blend-air door not functioning properly.

TEMPERATURE CONTROL

If temperature cannot be adjusted with the TEMP

knob/button on the control panel, the following could
require service:

(1) Blend-air door binding.
(2) Faulty blend-air door motor.
(3) Improper engine coolant temperature.
(4) Faulty Instrument Panel Control.
(5) Refer to the appropriate LH Body Diagnostic

Procedures Manual.

SUN SENSOR

The sun sensor is located so the sun hits the sen-

sor in the same way that it hits the driver and the
passenger. It is important that the area in front of
the sensor be unobstructed. Check that the following
items are not in the way of the sun sensor.

• Windshield wipers that are adjusted too high.

• Stickers on the windshield that are directly in

front of the sensor.

• Top cover which is not properly installed. The

sun sensor should be 1/4 inch. above the top cover.

• Caps or papers which might cover the sensor.
Refer to the proper LH Body Diagnostic Procedures

Manual for electrical test.

TEMPERATURE REFERENCE TABLE

Ambient

Temp.

Minimum

Floor

Outlet
Temp.

Celsius

Fahrenheit

Celsius

Fahrenheit

15.5°

60°

62.2°

144°

21.1°

70°

63.8°

147°

26.6°

80°

65.5°

150°

32.2°

90°

67.2°

153°

24 - 10

HEATING AND AIR CONDITIONING

300M

DIAGNOSIS AND TESTING (Continued)