Jeep 1996 Grand Cherokee Service Manual - page 1394
The ATC control panel also includes the ATC con-
troller. The ATC controller contains a microprocessor
and uses internal programming along with hard-
wired sensor inputs and messages received on the
CCD data bus network to control the many functions
and features of the ATC system.
The manual temperature control panel and/or the
ATC control panel/controller units cannot be repaired
and, if faulty, must be replaced.
SERVICE WARNINGS AND PRECAUTIONS
WARNING: THE AIR CONDITIONING SYSTEM CON-
TAINS REFRIGERANT UNDER HIGH PRESSURE.
SEVERE PERSONAL INJURY MAY RESULT FROM
IMPROPER
SERVICE
PROCEDURES.
REPAIRS
SHOULD ONLY BE PERFORMED BY QUALIFIED
SERVICE PERSONNEL.
•
AVOID BREATHING THE REFRIGERANT AND
REFRIGERANT OIL VAPOR OR MIST. EXPOSURE
MAY IRRITATE EYES, NOSE, AND/OR THROAT.
WEAR EYE PROTECTION WHEN SERVICING THE
AIR CONDITIONING REFRIGERANT SYSTEM. SERI-
OUS EYE INJURY CAN RESULT FROM DIRECT
CONTACT WITH THE REFRIGERANT. IF EYE CON-
TACT IS MADE, SEEK MEDICAL ATTENTION IMME-
DIATELY.
•
DO
NOT
EXPOSE
THE
REFRIGERANT
TO
OPEN
FLAME.
POISONOUS
GAS
IS
CREATED
WHEN
REFRIGERANT
IS
BURNED.
AN
ELEC-
TRONIC LEAK DETECTOR IS RECOMMENDED.
•
IF
ACCIDENTAL
SYSTEM
DISCHARGE
OCCURS, VENTILATE THE WORK AREA BEFORE
RESUMING
SERVICE.
LARGE
AMOUNTS
OF
REFRIGERANT RELEASED IN A CLOSED WORK
AREA WILL DISPLACE THE OXYGEN AND CAUSE
SUFFOCATION.
•
THE EVAPORATION RATE OF R-134a REFRIG-
ERANT AT AVERAGE TEMPERATURE AND ALTI-
TUDE
IS
EXTREMELY
HIGH.
AS
A
RESULT,
ANYTHING THAT COMES IN CONTACT WITH THE
REFRIGERANT WILL FREEZE. ALWAYS PROTECT
THE SKIN OR DELICATE OBJECTS FROM DIRECT
CONTACT WITH THE REFRIGERANT.
•
THE R-134a SERVICE EQUIPMENT OR THE
VEHICLE REFRIGERANT SYSTEM SHOULD NOT BE
PRESSURE TESTED OR LEAK TESTED WITH COM-
PRESSED AIR. SOME MIXTURES OF AIR AND
R-134a HAVE BEEN SHOWN TO BE COMBUSTIBLE
AT ELEVATED PRESSURES. THESE MIXTURES ARE
POTENTIALLY DANGEROUS, AND MAY RESULT IN
FIRE OR EXPLOSION CAUSING INJURY OR PROP-
ERTY DAMAGE.
CAUTION:
Liquid refrigerant is corrosive to metal
surfaces. Follow the operating instructions supplied
with equipment being used.
•
Never
add
R-12
to
a
refrigerant
system
designed to use R-134a. Damage to the system will
result.
•
R-12 refrigerant oil must not be mixed with the
R-134a refrigerant oil. They are not compatible.
•
Do not use R-12 equipment or parts on the
R-134a system. Damage to the system will result.
•
Do not over-charge the refrigerant system. This
will cause excessive compressor head pressure
and can cause noise and system failure.
In addition to the warnings and cautions listed
above,
the
following
precautions
must
also
be
observed whenever servicing the air conditioning sys-
tem:
• Recover the refrigerant before opening any fit-
ting or connection. Open the fittings with caution
even after the system has been discharged. Never
open or loosen a connection before recovering the
refrigerant.
• The refrigerant system must always be evacu-
ated before charging.
• Do not open the refrigerant system or uncap a
replacement component until you are ready to service
the system. This will prevent contamination in the
system.
• Before disconnecting a component, clean the out-
side of the fittings thoroughly to prevent contamina-
tion from entering the refrigerant system.
• Immediately after disconnecting a component
from the refrigerant system, seal the open fittings
with a cap or plug.
• Before connecting an open refrigerant fitting,
always install a new seal or gasket. Coat the fitting
and seal with clean refrigerant oil before connecting.
• Do not remove the sealing caps from a replace-
ment component until ready to install it.
• When installing a refrigerant line, avoid sharp
bends. Position the lines away from the exhaust, or
any sharp edges which may chafe the line.
• Tighten fittings only to the specified torque. The
aluminum fittings used in the refrigerant system will
not tolerate over-tightening.
• When disconnecting a fitting, use a wrench on
both halves of the fitting. This will prevent twisting
of the refrigerant lines or tubes.
• Refrigerant oil will absorb moisture from the
atmosphere, if left uncapped. Do not open a container
of oil until you are ready to use it. Install the cap
immediately after using. Store the oil only in a clean
moisture-free container.
• Keep service tools and the work area clean. Con-
tamination of the refrigerant system through careless
work habits must be avoided.
ZJ
HEATING AND AIR CONDITIONING
24 - 3
GENERAL INFORMATION (Continued)