Refrigerant System Leaks - Dodge 2000 DURANGO Service Manual

DN
DIAGNOSIS AND TESTING (Continued)
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the low pressure cut-off switch wire
harness connector from the switch on the suction line
jumper fitting.
(3) Install a jumper wire between the two cavities
of the low pressure cut-off switch wire harness con-
nector.
(4) Connect a manifold gauge set to the refrigerant
system service ports. See Refrigerant System Service
Equipment and Refrigerant System Service Ports in
the Description and Operation section of this group
for more information.
(5) Connect the battery negative cable.
(6) Place the heater-A/C mode control switch knob
in any A/C position and start the engine.
(7) Check for continuity between the two terminals
of the low pressure cut-off switch. There should be
continuity with a suction pressure (low side) reading
of 48 to 193 kPa (15 to 28 psi) or above, and no con-
tinuity with a suction pressure reading of 90 kPa (13
psi) or below. If OK, test and repair the A/C switch
sense circuit as required. If not OK, replace the
faulty switch.

REFRIGERANT SYSTEM LEAKS

WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE GENERAL INFORMATION SECTION
NEAR THE FRONT OF THIS GROUP BEFORE LEAK
TESTING THE SYSTEM.
If the air conditioning system does not cool prop-
erly, the A/C system performance should be tested.
See A/C Performance in the Diagnosis and Testing
section of this group for the procedures. If the A/C
system refrigerant fill is found to be low or if the sys-
tem is empty; a leak at a refrigerant line, connector
fitting, component, or component seal is likely.
An electronic leak detector designed for R-134a
refrigerant, or a fluorescent R-134a leak detection
dye and a black light are recommended for locating
and confirming refrigerant system leaks. Refer to the
operating instructions supplied by the equipment
manufacturer for the proper care and use of this
equipment.
An oily residue on or near refrigerant system lines,
connector fittings, components, or component seals
can indicate the general location of a possible refrig-
erant leak. However, the exact leak location should
be confirmed with an electronic leak detector prior to
component repair or replacement.
To detect a leak in the refrigerant system with an
electronic leak detector, perform one of the following
procedures:
HEATING AND AIR CONDITIONING
SYSTEM EMPTY
(1) Evacuate the refrigerant system. See Refriger-
ant System Evacuate in the Service Procedures sec-
tion of this group.
(2) Connect and dispense 0.283 kilograms (0.625
pounds or 10 ounces) of R-134a refrigerant into the
evacuated refrigerant system. See Refrigerant Sys-
tem Charge in the Service Procedures section of this
group.
(3) Position the vehicle in a wind-free work area.
This will aid in detecting small leaks.
(4) With the engine not running, use an electronic
R-134a leak detector and search for leaks. Because
R-134a refrigerant is heavier than air, the leak detec-
tor probe should be moved slowly along the bottom
side of all refrigerant lines, connector fittings and
components.
CAUTION: Never insert a leak detector probe into
the outlet for the optional rear overhead A/C unit.
Failure to observe this caution could result in dam-
age to the rear blower wheel and/or the leak detec-
tor.
(5) To inspect the evaporator coil for leaks, insert
the electronic leak detector probe into the center
instrument panel outlet and the floor duct outlet, or
near the outside of the rear overhead A/C unit outlet
bezel. Set the front or rear blower motor switch to
the lowest speed position, and the mode control
switch to the recirculation mode (Max-A/C).
SYSTEM LOW
(1) Position the vehicle in a wind-free work area.
This will aid in detecting small leaks.
(2) Bring the refrigerant system up to operating
temperature and pressure. This is done by allowing
the engine to run with the air conditioning system
turned on for five minutes.
(3) With the engine not running, use an electronic
R-134a leak detector and search for leaks. Because
R-134a refrigerant is heavier than air, the leak detec-
tor probe should be moved slowly along the bottom
side of all refrigerant lines, connector fittings and
components.
CAUTION: Never insert a leak detector probe into
the outlet for the optional rear overhead A/C unit.
Failure to observe this caution could result in dam-
age to the rear blower wheel and/or the leak detec-
tor.
(4) To inspect the evaporator coil for leaks, insert
the electronic leak detector probe into the center
instrument panel outlet and the floor duct outlet, or
near the outside of the rear overhead A/C unit outlet
bezel. Set the front or rear blower motor switch to
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