Wrangler L4-2.4L VIN 1 (2006)
Compressor Clutch Coil: Testing and Inspection
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. Begin testing of a
suspected compressor clutch coil problem by performing the preliminary checks.
PRELIMINARY CHECKS
1. If no diagnostic trouble codes (DTCs) are found in the powertrain control module (PCM), go to Step 2. If any DTCs are found, repair as required.
2. If the A/C compressor clutch still will not engage, verify the refrigerant charge level. If the refrigerant charge level is OK, go to Step 3. If the
refrigerant charge level is not OK, adjust the refrigerant charge as required.
3. On models equipped with the 2.4L engine, 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 current at the connector with the engine running and the A/Cheater control set to the A/C mode. If OK,
go to TESTS. If not OK, refer to the Body Diagnostic Procedures to perform further diagnosis. On models equipped with the 4.0L engine, go to
TESTS.
TEST
1. Verify the battery state of charge.
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 voltage, test the clutch coil feed circuit for
excessive voltage drop and repair as necessary. If there is no voltage reading at the clutch coil, use a DRB III(R) scan tool and refer to appropriate
diagnostic information for testing of the compressor clutch circuit and PCM control. The following components must be checked and repaired as
required before you can complete testing of the clutch coil:
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uses in the fuse block and the power distribution center (PDC)
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A/C-heater mode control
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A/C clutch relay
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A/C High pressure switch (4.0L engine)
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A/C Low pressure switch
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Powertrain control module (PCM)
5. The A/C compressor clutch coil is acceptable if the current draw is 2.0 to 3.7 amperes. 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.