Dodge ZB 2005, Руководство по обслуживанию

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mulator, the powertrain control module (PCM) in the
engine compartment, and the A/C compressor clutch
relay in the power distribution center (PDC). The
PCM may delay compressor clutch engagement for
up to thirty seconds.
The A/C compressor clutch components cannot be
repaired and, if faulty or damaged, they must be
replaced.
DIAGNOSIS AND TESTING
A/C COMPRESSOR CLUTCH COIL
The A/C compressor clutch coil electrical circuit is
controlled by the powertrain control module (PCM)
through the A/C clutch relay. The A/C clutch coil can
be tested by either measuring cluch field coil resis-
tance or by measuring current draw. Begin testing of
a suspected compressor clutch coil problem by per-
forming the preliminary checks.
PRELIMINARY CHECKS
(1) If the compressor clutch will not engage, verify
the refrigerant charge level (Refer to 24 - HEATING
& AIR CONDITIONING/PLUMBING - DIAGNOSIS
AND TESTING - REFRIGERANT SYSTEM LEAKS).
If the refrigerant charge level is OK, go to Step 2. If
the refrigerant charge level is not OK, adjust the
refrigerant charge as required.
(2) If the A/C compressor clutch still will not
engage, disconnect the wire harness connector for the
A/C pressure transducer and check for battery cur-
rent at the connector with the engine running and
the A/C-heater control set to the A/C mode. If OK, go
to COIL RESISTANCE TEST and/or COIL CUR-
RENT DRAW TEST. If not OK, refer to Body Diag-
nostic Procedures to perform further diagnosis.
COIL RESISTANCE TEST
(1) Disconnect and isolate the negative battery
cable.
(2) Disconnect the wire harness connector from the
A/C clutch field coil lead connector.
(3) Use an ohm meter and measure the resistance
of the clutch coil at the coil lead connector terminals.
(4) Refer to the A/C Clutch Coil Specifications
chart for the acceptable A/C clutch coil resistance.
Specifications apply for a work area temperature of
21° C (70° F).
(a) If the A/C clutch coil reading is below speci-
fications, the coil is shorted and must be replaced.
(b) If the A/C clutch coil reading is above speci-
fications, the coil is open and must be replaced.
COIL CURRENT DRAW TEST
(1) Verify the battery state of charge (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/BATTERY -
DIAGNOSIS AND TESTING).
(2) Connect an ammeter (0 to 10 ampere scale
selected) in series with the clutch coil feed terminal.
Connect a voltmeter (0 to 20 volt scale selected) to
measure voltage across the battery and the clutch
coil.
(3) With the A/C-heater control in the A/C mode
and the blower motor at low speed, start the engine
and allow it to run at a normal idle speed.
(4) The A/C compressor clutch should engage
immediately, and the clutch coil supply voltage
should be within two volts of the battery voltage. If
the coil supply voltage is OK, go to Step 5. If the coil
supply voltage is not within two volts of battery volt-
age, test the clutch coil feed circuit for excessive volt-
age drop and repair as necessary.
(5) Refer to the A/C Clutch Coil Specifications
chart for the acceptable A/C clutch coil current draw.
Specifications apply for a work area temperature of
21° C (70° F). If voltage is more than 12.5 volts, add
electrical loads by turning on electrical accessories
until voltage reads below 12.5 volts.
(a) If the A/C clutch coil current reading is zero,
the coil is open and must be replaced.
(b) If the A/C clutch coil current reading is above
specifications, the coil is shorted and must be
replaced.
Fig. 1 A/C Compressor Clutch
1 - BOLT
2 - CLUTCH PLATE
3 - PULLEY AND BEARING
4 - FIELD COIL
5 - SNAP RING
6 - SNAP RING
7 - SHIMS
24 - 10 CONTROLS
ZB
A/C COMPRESSOR CLUTCH (Continued)